Kensington Expert Wireless Trackball Mouse (K72359WW) Black, 3.5" x 6.1" x 8"

The reason I bought this trackball mouse may be different than others. ARCADE GAMING!!! More on that in a bit.. However, I have found that this is probably THE BEST accessory I have purchased for my computer(s) in many years. And that's saying a lot considering the number of goodies I have bought. I have 4 mice sitting here. All of them are wireless. 2 of them are gaming mice with many buttons, DPI changers, etc.. They all do exactly what they should do, and they do it very well. However, as one that uses my computer at times 20 hours at a time my hands can get very painful holding/using a mouse. I use an ergonomic keyboard and will NEVER go back to using a straight flat keyboard again. I had a trackball (wired) from Kensington many many years ago (like back in windows 98 era I think) and loved it. So I have had some experience with them. I did a couple days of research into which trackball mouse I would want. I looked at the finger ones, thumb ones, marble, full size, etc.. I read literally 1000's of reviews. (Just a hint, I ALWAYS read the negative reviews first. Show me the issues people have so I can decide if it is worth it, just in case....then show me all the positives.) The reviews of this one over many different sites sold me. And of course, since I buy via Amazon, I have NO ISSUES if I don't like it and want to return it. So, why exactly did I want one? Well, because I LOVE to play arcade games. And my favorite arcade games are old one like Crystal Castles, Centipede, Star Wars, Missile Command, Golden Tee (golf), etc. And to play these where they simple don't suck, you MUST use a trackball. Well, I sold my video cabinet years ago which had a trackball panel with it. So I thought I would give this a try as a replacement. WOW!!!!!! This is a dream when it comes to playing arcade games that utilize trackballs. The ball spins so beautifully and has exactly the right momentum force that the games play exactly how they are supposed to. As for use as a mouse for the PC? Again..... WOW! My hand does not fatigue at all, even after 10-15-20 hours of constant use when doing design work. I LOVE the fact that you can program the 4 buttons to do whatever you want PER APPLICATION!!!! In other words, you can tell it to use button 1 for this function in MS Word, and that function in Photoshop. And the scroll ring???? OMG I have fallen in love with this thing!!! While I wish I could use it in games that use a spinner (tron, arkanoid, etc.) I have not found a way to do that. It simply scrolls pages up and down. And can also be used for zoom effects zooming in and out. LOVE that feature. What makes it so much better than any mouse wheel I have used (and some of my mice are $$$$$) is that you can program the speed/range. Same with the ball speed. You can adjust it for how far it will move, acceleration speed, and how fast overall. I can't boast enough about this trackball. And while I got down to two choices....I am so happy that I picked this one. I am selling my mice now...(may keep one, just in case) but will never NOT have one of these trackballs on my desk.

This is a fantastic, well built track ball. I could always do with fewer wires on the desk so I love that it’s wireless and I can move it around. Bluetooth also worked great for me though I prefer to use the receiver since I switch computers often. I haven’t used a trackball in a long time but I wanted to try one and I have no regrets about trying this one. I have been using it constantly for the past week and I’ve got to say, I’m very happy with it. As far as ergonomics go, I’m not sure whether it’s better than my old mouse yet. I haven’t used a track ball in 15-20 years and it uses a different set of muscles depending on how you use it which has led to some muscles getting tired the first day. Being able to use it with my pointer finger, thumb, palm, or combination of digits, however, is a huge plus for me. I can adapt my grip for comfort or accuracy easily. It has a nice pad for my hand which I do like and is comfortable but sometimes prefer not to use as I’m used to having my wrist rest on the desk by itself. I also really like that the trackball stays in place and I don’t have to keep picking up my mouse to move it around. The scroll wheel also has a nice feel and I like I can scroll with my thumb, pointer, or middle finger instead of constantly using the same one and wearing it out. After a few days, I raised the sensitivity much higher as I felt the muscle control in my fingers was adapting. It may take a bit longer before I’ve really mastered this. As a side note, I tried a mouse accuracy test online and was able to achieve a slightly lower, but nearly the same, level of accuracy on the trackball vs a regular mouse. Even though I’m not regularly clicking circles on different sides of the screen often, I believe this ball can perform just as well as a regular mouse at any task. I even tried playing some FPS games just for the heck of it and it was fine, but I think it will take some getting used to before I prefer it. The hardware itself is beautiful. I love how it looks like HAL or a robot from Portal or something. The ball is a beautiful color. The cradle is rock solid. It goes well with the rest of my black colored accessories. The only negative for me, was the KensingtonWorks software on macOS Catalina. It was a pain to install due to security settings and required multiple reboots before it would detect the trackball. Even then it didn’t seem to update settings correctly. I should mention, Kensington support was phenomenal. They were available through chat right away and helped me get the software installed and working. Unfortunately I got sick of rebooting/troubleshooting and I ended up using another piece of software called BetterTouchTool that let me really jack up the sensitivity and assign Mission Control to the top buttons, a setup I’m quite happy with. I also turned off mouse acceleration on Mac since that gave it a weird feel I didn’t like. On my Windows machine, the KensingtonWorks software installed just fine, although I have noticed I can’t jack up the sensitivity any higher in KensingtonWorks which I’ve wanted to do after developing finer muscle control in my digits. I’m sure I will find a way when I get around to it. Overall, if you want a great wireless trackball, this is an excellent choice. You won’t be disappointed.

I gave it 4 stars because nothing is perfect. Here's my experience. I have used the smaller Kensington Orbital trackball (perfect ergonomics) for almost twenty years in my Digital and Print Production work and into my retirement. I have no idea how many miles of clipping paths I've drawn over the last twenty-five years with a mouse or a trackball. I usually had to replace the Orbital every two to three years because of the mileage. For a long time I have considered the Expert wireless as a replacement because of the additional 2 programable buttons and Bluetooth. But after reading the negative reviews, the Expert seemed too awkward to use, and I would buy another Orbital. I finally took a chance on the Expert Wireless, and without too much adjustment, I do not regret the purchase. There definitely is an adjustment, but then I'm left-handed and have been adjusting all my life to right-handed tools and devices. The beauty of the Kensington Orbital and Expert trackballs is the symmetry and programability. Now for the adjustment period (please refer to uploaded photos). 1. Side view of both to illustrate difference in ergonomic hand to ball position. As you can see, the older version fits perfectly in the palm of your hand with at a comfortable position for movement. You absolutely need the wrist pad for the Expert. 2. The Expert Wireless requires more desk space. 3. On the Mac, disregard removing the Bluetooth USB dongle from the battery compartment. Check your Bluetooth settings for ExpertBT5.0 that confirms your trackball is connected. The software install an App in your Applications Folder with a Preference Pane in the System Preferences that will launch the app. 4. You must enable the 'KensingtonWorksHelper' in the System Preferences/Security & Privacy/ Otherwise you will not see any programable settings in the Trackball preferences. 5. The software asks you to link your preferences to either Dropbox or Microsoft OneDrive. Since I have both I didn't ask any questions about alternative local prefs. 6. The major ergonomic consideration for me is arm/hand position height relative to the arm of the chair. I like to have the chair support my elbow and have my hand fall effortlessly on the trackball so all movement is in the wrist without strain. For me, this requires the keyboard tray to be about 25" from the floor, while the desk surface is a normal 29" from the floor. 7. I have program the bottom right button for a single click (thumb). I found that the lower left button was too awkward for what is considered the right-click. So I use the upper left button and my middle finger. this seems natural to me. 8. I find the scroll wheel not useful compared to scrolling with Magic Trackpad. It's not in the way, so it's not a problem. 9. Yes, you do have to wake up the trackball after the Computer has been in Sleep mode. That's a function of being wireless. I've been using the Expert now for almost three weeks without a problem. So far, so good.

First I want everyone to know I have used a wireless mouse for years. Second, for most of those years, it has been a Logitech Trackball. I have been thru four of them. I work from home, and I think I just wore them out. Logitech is a great mouse. I have no regrets there. Then the other day, I left my home office for an appointment and when I returned home a few hours later, it was like my electronics went haywire. My mouse, dead. I mean dead. Not battery dead. But dead, dead. Every one of my Alexas, spontaneously disconnected from the wireless internet. Wireless Keyboard - also dead - but just the batteries - I had replaced them about a month ago, and traditionally replace them once a year on average. There was no power outage. and I have everything on surge protectors. My computer was fine. It was the peripherals that were winking out on me. It was bizarre. I thought maybe it was just time to investigate a new mouse after using my backup muse for half the day and literally wanting to huck it out the window. I read blogs and reviews. This Kensington Mouse was rated the number one choice for people in my industry, and to be clear, I was hesitant. I had been a loyal Logitech user for years. But with nothing to lose, I took the plunge, made this purchase - and KNEW I would know within minutes if I would like it or revert back. I received it less than two days later. Shipping was hyper fast. The pairing was incredibly easy. Getting it out of the package was harder than the pairing process, and it came with 2 batteries in the package. Because of my wireless habit, I always keep a healthy supply of batteries on hand, but it was nice to have them encased. Within 20 minutes of delivery I had it A.) out of the box, B.) Paired to my PC, and C.) Software downloaded and buttons custom configured. SHA-ZAM! I can absolutely tell you within minutes I am loving it. I thought the scrolling ring would be a bit tough to adjust to, but no. The scroll feature is probably one of the best things I like. No regrets. If you're on the fence - work in the tech industry, YOU WILL LOVE THIS MOUSE. I can't attest to gaming use, but then I'm not a pc gamer. Without hesitation- I know this will be my new go to. So worth the money.

This mouse runs like a dream, I don't usually write reviews but this deserves it. I started having a lot of wrist and elbow pain from using a traditional mouse and did some research on more ergonomic trackballs, I went through a few of the major ones until I landed on this one. The wireless Kensington expert however is a joy to use, the extra buttons once you get used to them change your experience for the better. Pressing two buttons for a third function honestly blew me away, it's not an exaggeration to say my browsing experience is an absolute delight, I LOVE the scroll ring. It's highly customizable so you can adjust the speed of the trackball and the scroll ring, you can set the buttons to do different things depending on what application you're using, it's hard to imagine life without this feature now. This is truly my most prized material possession. Going back to a laptop trackpad or traditional mouse or god forbid a thumb ball is an agonizing, hellish experience. My only quibble is that I dropped and broke my first Expert and had a lot of trouble getting it fixed product support was next to no help, I ended up having to pick up another one but its well worth it. I would say if you're not prepared to commit a Benjamin for a computer accessory, try to get an open box or gently used Expert on ebay. I've tried vertical mice, thumb balls, elaborate gaming mice, all pale in comparison to the ease of use of the Expert. I don't do a lot of high intensity gaming and if I do I'll use a gamepad but for most gaming like RTS/MMO/MOBA it worked absolutely fine if not better than a traditional mouse. If you're looking to play FPS you may want to look at the Kensington Orbit as that kind of trackball as that kind of mouse is more suited for gaming. I was suffering from carpal tunnel and repetitive stress injuries and this mouse causes me no pain, in almost any position it's extremely comfortable to use, I recommend you try the Expert if you're in pain from the sweeping motion and positions that come with using a traditional mouse.

You buy a trackball - it's like buying a mouse, right? Plug and play. Even wireless. Oh, don't be so droll. Kensington has finally micro-managed itself into the pit of ineptitude from which I fear there is no escape. They may be on their final downhill slide. I own Kensington products. I've purchased trackballs from them since the 1980s. Yes. Perhaps since they started making them. All with a cord. All very happy. And why not? They did everything right. But I was feeling sporty and modern. I generally don't like wireless devices as they occasionally exhibit a finicky side I don't enjoy in computer work. But this setup may have benefited from a wireless device. I was so stupid. Plug it in. Yes it works slowly. Kensington USED TO include the drivers. Nope. Not anymore. Those days are gone. No matter, I have other trackballs - i'll use THAT copy of drivers. Nope. Can't recognize it. Go get the LATEST driver, you stupid customer. Okay, I'll do that soon. Then i notice the wireless is inferior. Yes, it's without a wire, but no, the reception makes it unusable. It's only line of sight. It may as well be an old infrared unit. Line of sight works great. Behind anything at all (including flowers), it skips, stutters, and pauses. Worthless. Far below what I once thought was Kensington quality. New batteries? Nope. No change. Still a mess. Okay, let's do the driver thing. Downloaded -- a bit of an unfriendly chore by itself -- and install. But wouldn't you know it?? "This version of Windows requires a digitally signed driver." (W7) Can't use it. It's their driver, off their site, d/l this very day, but they're apparently not trustworthy enough for windows to work. Now, of course, the device doesn't work at all -- after 2 more reboots and tweaks - what with Windows having isolated the driver and even warning me about it. It's going back. The reception is rubbish. The software is insane -- and that's good ol' W7 and it STILL won't work. Kensington has jumped the shark. They no longer make products for people to use, but simply bait for fish to bite on. It SHOULD have been 1. plug and play. 2. exceptional reception. 3. no-glitch software. 4. a happy-to-give-you-the-drivers-we-require website. If you're looking for any of this, do not buy the wireless version. Do not buy from Kensington. Love my other Kensington trackballs.

I've been writing about - and reviewing - trackballs for decades -- probably more than 30 years. I've been working with trackballs since the days before they were using the oxymoron 'trackball mouse.' A trackball is NOT a mouse. It's a trackball - it does some of the same things as a mouse, but it ISN'T a mouse. It's like 'car bicycle' Both get you from point A to point B, but you really can't confuse the two. Trackball mouse is just stupid marketing speech. Anyway - back to my review. I've been using trackballs for a LONG time. I don't like to use a mouse - it takes up a lot of desk space, it requires a lot of arm movement, it usually requires a smooth scrolling surface, the buttons have stopped working (on the mice that I DID use). I prefer a trackball over a mouse. I prefer a trackball over a touch pad. I've used the Logitech thumb mouse - and it was my 'go to' device until I got a wired Kensington trackball for a then 97-year-old friend who didn't have the muscle control to use a mouse. I used that trackball, too, and fell in love with the scroll wheel. Even though I didn't want a wired device, I bought one for myself. I got tired of pulling the wire when I walked away from the computer, and it got tangled under my foot. I wanted a wireless alternative that was similar to the wired Kensington trackball that I had been using ALL THE TIME. I realized that this wireless trackball was heavy. I realized that this wireless trackball was large. I realized that this wireless trackball had a massive ball. After it arrived, I had to figure out how to insert the batteries (there's a notch in the battery slot in the case for the Positive end of the battery - you angle the negative in first, then slide the positive end down. Once I figured that out, it was easy. I didn't see a dongle in the box, so I concluded that the dongle was in the battery compartment -- it was. Bluetooth didn't pair. Instructions weren't very helpful. In the case of bluetooth for this trackball, I suspect that the signal from my bluetooth dongle is too weak to talk to the trackball. For me, it doesn't matter - radio frequency works fine. I use my trackball differently from most users -- it's sitting on my right leg, near the knee. It's hefty enough that it won't slip off. The angle isn't a problem for me. The scroll ring on this trackball is very smooth - perhaps Kensington has resolved the issue that others complained about in their trackballs. I would have preferred larger 'nubs' on the top of the scrollwheel, like some other Kensington products, but have gotten used to this scrollwheel. (Tip - for scrolling a large area, you can hold your finger on the wheel, lift your hand, and scroll the wheel around the ball). The ball and buttons work fine for me - I click the lower left button with my thumb, and the upper right with my right ring finger. The top left and lower right buttons haven't gotten much use, yet. I've configured the buttons with the Kensington software, but it didn't seem to want to make top left into a middle button and lower left into a click. I'll work around it. I've only used this for a few hours. I can't comment on durability or battery life. I'll probably append to this review after a few weeks or months of use (assuming it doesn't fail in the meantime and I wind up returning it). For now, it's probably my pointing device of choice. If that changes, I'll report on it. A few more things -- I'd prefer that the mouse was held in, somehow, so that I don't worry about it dropping out. I'd like to see Kensington and Logitech getting together on the one aspect that they could really work on -- to help the user, set up the protocol that lets the Kensington wireless products work with the Logitech Unifying Receiver -- I'm using Logitech with two thumb trackballs, and it would be great to NOT have to dedicate a USB port to the Kensington USB dongle when I've got a perfectly good USB dongle for the Logitech products. DO YOU HEAR ME LOGITECH? DO YOU HEAR ME KENSINGTON? DO THIS FOR THE CUSTOMER -- IT'S GOOD P.R., AND GOOD TO PROMOTE STANDARDS UPDATE - ONE WEEK LATER (9 20 18) At first, I thought that this trackball was great. After a few days, it started skipping - I'd move the ball, but nothing happened on screen (this was, of course, AFTER it woke up). I tried blowing dust out of the area where the ball rolled, I tried wiping the ball with a cloth - this didn't seem to help. It seemed at times that I couldn't roll it from the top - I had to roll from an area just above the scroll wheel. I've had issues like this with other trackballs, but I'm not sure what resolved them (if they WERE resolved). I'll give this a few more days, try contacting Kensington, and may wind up - even though I'd prefer to keep this ball if it worked properly - returning it for a refund. I've deducted a start for now -- if I can get this to work well, one or more stars may come back. The bluetooth doesn't work, either. I called Kensington Tech Support and theyre replacing the trackball -- I'll report on the new one, after I've tested it for a while.

So good I just bought another one for my wife. I suffer from tendonitis in my right thumb. I've been using a Logitech Performance MX mouse for years and it has been very good. However, lately, my thumb has been experiencing more and more pain as the day goes on, most likely due to my claw grip on the mouse. I have somewhat large hands and have always felt mice are too small for me. I decided to try a trackball. Now in Day 2 of using this trackball, I am kicking myself for not having tried it sooner. 1. This thing is huge, but it ends up taking less desk space than my mouse because it doesn't require any room to move around, it simply sits there. 2. The ball is as big as a pool ball, but it has a nice weight and rolls nicely. I've noticed that rolls much more easily in Day 2 than it did when it first came out of the box. Probably due to finger oils as other reviewers have mentioned. 3. The wrist rest feels fantastic to me. Someone said the fingers are supposed to hover over the trackball but I rest my fingers on the ball and just move the ball around. The palm is nearly horizontal and the wrist in nearly straight, thanks to the wrist rest. I'm pretty sure that this is ergonomically optimal. Because of this position, manipulating the trackball takes minimal effort, movement and energy, in contrast to a mouse which requires constant moving, picking up, and repositioning. 4. It didn't take me more than a day to get used to the trackball. I'm a middle aged guy so learning new tricks isn't as easy as it was when I was younger. But here in Day 2, I can now move the pointer around 4 large monitors far more easily than I did with a mouse. Almost everything I could do with a mouse is easier with a trackball. 5. The mouse remains nearby and connected. Anytime I want to revert to a mouse (maybe for gaming), it's not a problem. But for productivity tasks, it's 100% trackball for me. 6. The scroll wheel is probably the weakest part of this device. It doesn't spin smoothly, but feels gravelly and friction-y. When I turn it, it feels cheap and not well-made. Nevertheless, I have no problems using it and still prefer it hands down to the scroll wheel on the MX Performance mouse as it feels more natural to turn. Moreover, I have set up the buttons so that when I click the two bottom buttons simultaneously, I can scroll around the browser lightning fast just by moving the trackball. Here at the end of Day 2, my thumb has NO pain (after months/years of constant pain) in the resting position (If I pull or stretch my thumb, there's still pain, but we'll see if even that goes away over time). This trackball has earned a place of honor on my computer desk. Consider me fully converted to the track ball.

Why, why did I wait to buy one of these it's beyond brilliant. First up let me explain, about 3 months before buying this I had a fall and broke my wrist, broke 2 bones and did some ligament damage - ouch, yes it's as painful as it sounds and if you take nothing else away from this review be careful with icy pavements. The healing from a broken wrist can take up to a year in some cases and a lot of pain ensues while thats happening, when I had a cast on for 6 weeks towards the end there was no discomfort hardly at all so in my head it's yay, cast off, back to normal, rock on. Er no, as the cast came off my reaction was mm ow ow OW OW! MOTHERFU.... that hurts, and so began a quest to find someting I could use comfortably and get my extremely bored arse back to work. So finally, the trackball itself, what can I say, silky smooth operation from the actual ball, being 55mm across it means you can control it with three fingers if needs be, the four buttons around the ball are totally customisable if you download a small application from Kensingtons website and you aren't limited to four functions either, you can add keys to each button so you get a different function if you press shift, or control, or alt or the win key so four individual functions on each of four buttons - that's a lot of shortcuts. In addition to this you can specify a set of shortcuts for each application, the combinations and permutations are mind boggling. There is also a scroll wheel right next to the ball and again it's customisable in terms of speed and direction and inertia which I tried but didn't like but it's worth looking at it to see if it works for you. There is of course the usual pointer speed control which using a super ultra wide high resolution monitor I have set quite high to quickly move around the huge screen area, that is fine but it's not the most precise method - however Kensington have thought of that too, you can set one of three keys to instantly and temporarily lower the pointer speed making precision a doddle, there is even a setting to lock the movement to just vertical or horizontal movement in a single axis and while this might not sound like the pinnacle of technology if say you have a bunch of tabs open in a browser or are going through a bunch of drop down menus in a professional application such as Photoshop or illustrator - which I do all day every day while doing actual work it just makes it even easier - hence quicker to use. It's just one more reason to like this trackball and why I will NEVER go back to using a mouse again - ever. Looking at one of the other reviews there was a criticism that you had to float your arm to use the trackball and it placed strain on your arm/wrist - well as this was the entire reason I'd been looking at things like this trackball to reduce just that and allow me to get back to work take a look at this... https://www.amazon.co.uk/gp/product/B0752MCX82/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1 It's basically a device that clamps to your desk and cradles your arm taking the weight and strain away from your arm - and crucially for me the wrist, a combination of that cradle and this trackball means I have a perfectly straight arm position from the elbow to fingertips and the sometimes unbearable pain of using a mouse - and i've tried 6, everything from gaming mice to really thin bluetooth mice to smaller sized mice, even a vertical mouse has gone, I can use this for hours with nothing more than the odd twinge - using a mouse all day I'd have to mainline so many painkillers it'd turn me into a zombie. Very seldom do I buy anything that makes a real improvement to my daily life but this is definitely one of those times and I don't like this trackball I love it.

J'ai acheté cette souris trackball, après avoir utilisé pendant des années des souris ergonomiques classiques. J'avais avec celles-ci tout de même quelques gênes à l'usage. J'ai acheté ce trackball après avoir lu les avis. Je ne suis vraiment pas déçue. C'est la souris la plus ergonomique que j'ai utilisé. Aucune douleur, aucune gêne. Elle est très agréable. Je ne pourrais clairement plus revenir en arrière.

A trackball is nothing I would have considered in the past as most of my PC time is used for gaming and being able to do work has always just been a "bonus" of the platform. However, over the course of the wonderful year of 2020, I had to find solutions to working from home and purchased not just one, but two trackballs. I first started with Logitech's M570 (wireless) and followed it up a couple of months later with the Kensington Expert Wireless. Chances are that if you're seriously considering transitioning to a trackball, you are looking at exactly these two models or their wired siblings. Both solved a very simple problem of making the most of confined space. For my gaming and personal PC, I have a typical desk setup with a brick of a gaming mouse, but for the work laptop I lugged home with me, the idea was that it was a temporary thing and I'd be back in the office with a full desk in no time. Three quarters of a year later and the work machine is growing roots in an old TV table. I managed for a very long time as I was quite comfortable with simply using the built-in trackpad, but when they replaced my machine with a new one, I could no longer work without wanting to throw it out the window. The 'brilliant' minds that designed the new trackpad clearly never used one as they removed the physical buttons that bisected the pad and made the pad itself one giant button that would only right click if you used the very bottom right corner. So now I needed a mouse, but TV trays don't have the runway for effective mouse use. Enter the trackball. Since trackballs stay put, they can sit comfortably in a small space and you still have full use of your cursor. The second thing both trackballs solved was the right-click issue. While the M570 has more traditional placement of buttons like a regular mouse, the Kensington Expert (herein "Expert") has four fairly large buttons that can be tapped easily regardless of what hand position you take. Since the laptop's trackpad cut the right-click distance by 2/3rds and I live and die by context menus, I needed that functionality without feeling the need to break equipment. The above issues are solved by pretty much any trackball device available in the market today, so what it really comes down to aside from general reliability and longevity is preference. First off, while the M570 seems sturdy enough, the Expert feels like a tank. It has a fairly large footprint compared to the relatively mouse-sized M570, but the Expert also has a much larger ball (maybe three times bigger?) and is heavier and kept in place with rubber feet. As mentioned above, it has four large programmable buttons surrounding the trackball and a rubbery ridged wheel that provides you with your scrolling (compared to Kensington's Slimblade which has you twisting the ball in the socket to scroll instead). The Expert uses the bottom left button (by default) for left click and the bottom right for right click. Since the ball is finger operated as opposed to thumb-operated M570, you typically use your thumb and pinky to click and right-click respectively. It takes some getting used to, but it really becomes second nature pretty quickly. On top of that, you get two extra programmable button assignments by clicking the top two or the bottom two buttons together. Despite its wider footprint, the Expert has become my go-to device for work while the M570 has been repurposed for the media machine I have connected to my TV. While it comes with a very sturdy wrist pad to help with your ergonomics, since I sit higher than the Expert instead of level with it, I find it feels better without the pad attached. The larger ball is much easier to manipulate and makes more logistical sense than when using the thumb ball of the M570 and Kensington's software allows you to set up keyboard hotkeys to assist with accuracy. For example, I can hold the Ctrl key to drastically slow down the cursor (this is completely customizable) so I can select specific things or position the cursor with precision. For cleaning, the ball is held in the device by gravity only and can be easily lifted out without having to lift the base unit (and it's kinda fun to do that anyway). Underneath you'll have access to the sensor as well as the three beads or skates that the ball rides on. I don't find that the ball is a dust magnet, but normal use will see crud accumulate either on it or on the skates. It's easy to simply lift the ball and give everything a wipe down. There's only two things that I am nitpicky about when it comes to the Expert. First, the ball has a very high profile (exactly half of it is exposed) and while I find it very comfortable to use throughout the day and experience no wrist strain whatsoever, it would have been nice if the 'horizon' or the plane of the base unit was a bit higher and the ball sunk a bit lower (things addressed in the Slimblade). The second thing is that this thing puts itself to sleep, which is admittedly a good thing. However, you cannot wake it by rolling the ball or scrolling the wheel; you must click one of the buttons to wake the device from sleep, but the click is actually registered with the OS and is not thrown away. Therefore, unless you're expressly positioning your cursor safely when you go idle, then you need to be careful on what button you press to wake your device. Neither are dealbreakers, but I really find the registration of the wake input to be weird. Overall, I am very happy with both of my purchases, but the Expert won out as my day-to-day solution for work. I would never use the device for gaming (at least competitively), but its customizable configuration from speed to keystrokes with Kensington's lightweight software easily make it a power-user's device. It may be unintuitive at first, and I was always first in line to mock these devices, but I have completely turned around on them. I think wherever I go in my professional life, the Expert will come with me.

Initially had some software problems which is fixed with updates, now it works without any issues. I tried all sorts of trackballs and found the larger the 'ball' the better, and this is certainly the biggest in the market I can find. I tried thumb trackballs, but they 1. sores out my thumb joint fast and 2. impossible to clean as the balls are 'locked' in the socket (at least when I was using the Logi Trackball mouse). I prefer the trackball because I move it with my middle three fingers instead of the thumb, the movement is shared, and also requires far less movement on my fingers than if I use the thumb alone. The tracking works wonderfully well (after the software update), and I can scroll up and down pages easily with my ring finger. All in all, after 20 years of trackball use (used Logitech Trackman the most prior to this), this is definitely the best in terms of accuracy, ergonomy, functionality that I've come across. Highly recommended.

I have two of these, one for home use, and one at the office. Never going back to a mouse again. I have tried a couple of difference trackballs with smaller balls, they are nowhere near as good. Good points: - Very accurate thanks to the large ball. Any trackball takes some getting used to, but after a short period of adjustment, the accuracy is comparable to a regular mouse. - Lots of travel for my triple screen setup. Other trackballs were a PITA when having to move from left to right monitor. - Smooth! - Scroll wheel works very well after some use - Very comfortable, no more wrist twisting, do everything with just 3 fingers - Looks pretty good - Easy to clean It is not without its faults, but they are minor issues: - The scroll wheel is very scratchy initially. This mostly goes away after a couple of weeks of daily use though. Even then it could be little more smooth, maybe this is something Kensignton can improve in future models. - The trackball falls out if the device is not kept upright. Not normally an issue, just something to be cautious about. - Wireless is pointless for something that is clearly stationary and only uses battery (although the battery life is very good regardless, I've had these for months, no battery change yet). - Somewhat pricy although I paid more than Amazon sells them for now. It is definitely worth EUR 90 - The wrist wrest is a must. Ideally it would be one piece, as it is it comes off a bit too easily - Gunks up. Really need to clean with some tissue once a week to retain smoothness. Doesn't affect accuracy though, as a laser is used and the working is not mechanical. Overall I love this product and would recommend it to anybody using a desktop PC.