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- Verified Buyer
I like this mouse better than the Logitech MX 610 Left-Hand Laser Cordless Mouse, which it replaced. The unusual sideways orientation of the Evoluent looks strange, but it took no time getting used to. It promotes a very relaxed and natural hand and wrist posture. It looks like your fingers are lined up vertically, but in reality, your fingers are positioned in a gentle arc and your hand is turned inwards by a few degrees. Your thumb rests in a chrome-looking divot.The Evoluent 4 design has a bottom "lip" that prevents your pinky finger from rubbing against the desk. I can confirm that it works beautifully and adds to the overall comfort. It helps you to position your hand correctly. I also find that proper chair height (in relation to your desk) and wrist support is essential to keeping the arm and wrist straight. It also has a very long cord, approximately 6 ft.Your index, middle, and ring fingers align with buttons 1, 2 and 3. Between buttons 1 and 2 are a scroll wheel (with notched movement). The scroll wheel can be clicked as another button. Above and below the thumb are two additional buttons that could be used for back/forward functions in your favorite browser, bringing the total button count to 6, and they are all programmable under Windows (a non-WQHL-certified 32-bit and 64-bit Windows driver are included in the box on a small (mini) CD. The purpose of the drivers is to assign custom actions for the buttons. You can even assign actions to a combination of the thumb and finger buttons when pressed simultaneously. Mouse sensitivity is controlled by its own dedicated rocker buttons located where it cannot be accidentally pressed.Note: Even though the Evoluent Windows drivers warns you to uninstall any previous mouse drivers to "prevent conflicts," I ignored that and kept my Logitech drivers (SetPoint). Both mice work fine. I can actually still access the SetPoint drivers through a tab in the Evoluent drivers setting page. Nice.The Evoluent's sensitivity is indicated by 4 LEDs located at the top of the thumb divot and correspond to four hard-wired sensitivity settings. The lowest sensitivity is around 400cpi, while the highest feels like around 2000cpi (these are my estimates obtained by comparing it with other mice; it is not specified by Evoluent). I operate it on the 2nd-lowest setting, which is about 800cpi. The nice thing is that the sensitivity function does not require special OS drivers, so it works right out of the box on any computer and any OS. The mouse even remembers the last sensitivity setting used when you unplug it. The sensor is an eye-safe infrared laser. Even though it is not sold as a "gaming mouse", the Evoluent 4's sensor performs as well as gaming mice in both speed and tracking under high-acceleration. That is more than I can say for the MX 610.There are no Mac OS drivers supplied by the company, although third-party drivers exist for reprogramming the buttons (links are provided on the Evoluent product page). On Mac OS X, I did not install the third-party drivers, so I could not assign any special functions for the buttons. Out of the box, the button under your index finger is mapped to the "left button" (primary on a right-handed mouse). Button 3 under your ring finger is mapped to the "right button" (secondary). Button 2 (middle finger) brings up the Mac OS X dashboard, and the top thumb button triggers Exposé. The bottom thumb button and the mouse wheel button do nothing.The mouse is light enough and sensitive enough to push around with just your wrist; you don't have to move your whole arm. You can even steer it with just your thumb and finger tips. This is the secret to its comfort. It encourages you not to grip the mouse with any tension. You don't need to. With conventional mice, even ergonomic ones like the Logitech, I eventually find myself gripping the mouse with just the ring finger and thumb, and that creates tension and fatigue within an hour of use.The downsides are minor. The buttons don't require much force to click. While I like the light touch, it's sensitive enough that just reaching out and wrapping my hand around the mouse will sometimes result in unwanted button clicks. This is not a big problem, but I have noticed a minor increase in accidental clicking since I began using the Evoluent. Maybe I am still getting used to it. I can pick up and reposition the mouse while resting my fingers on the buttons without clicking those buttons, so it is not hair-trigger sensitive.Also, the dark gray part of the mouse where your palm touches is covered in a "soft touch" coating. While it feels nice, this type of coating is not very durable in the long run and will start to breakdown after several years, becoming tacky to the touch, or it can rub off at the points of frequent contact. This is probably why the pamphlet in the box warns not to use solvents or cleaners on the mouse, only a damp cloth. I wish companies would stop using this coating.Its unusual appearance also makes it a great conversation piece.Bottom line: if you're thinking about buying this mouse, buy it!