I’m a longtime user of Logitech trackballs, including their flagship MX Ergo Plus, but with two carpal tunnel surgeries, I’m always on the lookout for innovation in the trackball space. After purchasing a ProtoArc EM01 trackball and using it for a couple of weeks, the Kensington Pro Fit® Ergo Vertical Wireless Trackball caught my attention with its 60-degree vertical orientation, which positions the hand in a safe and natural “handshake” orientation for maximum comfort. The ProtoArc’s 20-degree orientation was one of the reasons I bought it, but the Kensington not only had a greater angle but was fixed rather than adjustable, which I like since I never change it. I tried a vertical mouse recently, and while I liked how it positioned my hand, manipulating a mouse felt awkward after years of using trackballs. My limited desk space meant I was constantly picking up the mouse and repositioning it to move the cursor. The Kensington trackball offers the hand position I prefer, similar to the vertical mouse, and it stays put on my desk. The silicon pads at the bottom of the trackball grip my desk firmly; this trackball isn’t moving!Despite Kensington being a well-known and generally reputable brand, some reviews about the scroll wheel, trackball movement, and cursor control concerned me. However, I have no issues with either of these items; I sense no difference between this device's cursor movement or trackball smoothness and any others I’ve used from Logitech or ProtoArc. Perhaps I’ve used trackballs for so long that I’m more tolerant of their feel and motion. I did change the trackball to a third-party one I like and already had in my possession, although the original trackball worked just fine. If you don’t like the cursor movement or precision, there’s a DPI button at the bottom to adjust the speed.I should add that the white and gray colorway matches my desktop decor, so that’s a bonus. Another nice touch is the button at the bottom that ejects the trackball for cleaning or swapping. It beats using the blunt end of a pen or pencil to poke the ball out of its socket!One more item of note. It takes two AA batteries, which is a deal-breaker for some people. However, after having an internal rechargeable battery on a Logitech device that failed to hold a charge after an extended period of use, I prefer replaceable batteries. Rechargeable AA batteries are always an option.I have only been using the trackball for a few days, but I’m pretty satisfied with it. If anything changes, I will report back.

Got this as my office offered an ergonomics assessment if we wanted it, and awesomely offered reimbursement for recommended items (of which they suggested a vertical mouse).My desk space in office is a bit cramped and I've been using ball mice for awhile (non-standard style, one large ball resting in the center of a base, also Kensington). Got this because it's literally one of like, four I could even find, and the only one of a reputable company. Plus work was footing the bill, so no need to go for the cheapest option.Overall, it functions exactly as expected. Control the ball with your thumb, has a vertical resting position for your hand, check and check. Nice extra buttons for your fore finger, and one button controls the wireless setting (one dongle wireless, two bluetooth, so you can have 3 devices connected to swap between).Ball sensitivity seems to be a bit poor, at least compared to my longtime go-to trackball, the M570. I used that for several years at home and in office before switching jobs to this one, where I changed to the Kensington big kahuna ball one (forget the name). Fortunately my job does not require much more precision beyond closing a window, but occasionally I need to highlight certain words preceisely or something more fine tuned, and it can be a bit annoying to deal with.A part of this is also the verticality. It's jarring coming from a regular mouse to vertical, and I switch back and forth daily, as my home mouse is a "standard" style Razer mouse. The advantage to this mouse in that area is the fact you aren't moving it around like a regular vertical mouse, so the hardest change to deal with is almost a non-issue.It's fairly comfortable, I took a bit of a risk as some said it might be a tad small for large hands, but it hasn't been too bad for me, maybe slightly smaller than I'd like. The buttons were also criticized, as the wireless selector button is often cited as being poorly placed, so people change the setting while working normally. I have not had this, and it requires you to hold the button down for a second or two, so errant clicks shouldn't cause any issue, my guess is their resting position may be falling upon the button, but I can't speak beyond my experience.The Kensington software has some quirks, I personally don't use it. You don't need it to run the mouse, it's only really for remapping the buttons, but they do what I want by default (forward/back is plenty for general use for me). I used it with the big ball mouse for awhile, but then I realized the software was updating my system preferences for mice outside of what I wanted, if I recall it was changing the scroll sensitivity, and even if you changed it, it would override after a short while. That took awhile to diagnose, and I uninstalled it once I figured it out, not worth the hassle.Overall, this is a great mouse if you want the specific combo of vertical and trackball, as it's a narrow category. If you just want one or the other, this is not the right mouse for you.

Regarding ergonomics i would greatly benefit from a left handed Version of this trackball.The scroll wheel on all of my vertical trackballS by Kensington are malfunctioning. It change the scroll direction randomly, to the point that I am unable to use the scroll wheel at all.I do not like that I am unable to set up different button actions for Bluetooth connections to the same computer, or even the 2.5 connector, I also am frustrated that Kensington works doesn’t recognize my three devices as individual devices, so cannot set up different accessibility functions by device either.

I have always preferred a trackball over a mouse when I have to work at a computer for most of the day. This particular trackball by Kensington comes with programmable buttons that can be helpful with routine tasks on the computer.

I really liked the ergonomic feel of the mouse and the convenience of the switch button being on top so I don't have to flip the mouse to change devices. (Why do companies insist on putting that switch underneath the mouse??)But unfortunately, the scroll wheel is complete garbage. It scrolls wildly and randomly when using it. So much so that I had to start using the scrollbars to move around web pages. I have shelved this mouse after trying to fix the wheel for 6 months now. (Note purchase date)Too bad since the rest of the mouse is good. But I use the scroll wheel extensively.

The button placement is weird, keep hitting the bluetooth / wireless buttons and disconnecting myself. it feels like cheap plastic but hey the scroll wheel works under linux at least.There must be something better out there.

I haven't used a Kensington trackball since the 90's. I'm pleasantly surprised, it works great and feels great.

The mouse was working fine for like one month, then has stopped working due to no connection to the desktop via bluetooth. The customer service via Amazon is pretty lame, no replies at all.