Bests & Worsts Reviews from Amazon

As a longtime trackball user (with one of my favorites being an older model of the Kensington Expert mouse) I was very excited about this one. The features were outstanding, the trackball movement and precision flawless, and the scroll ring was very useful. However, the trackball housing itself is constructed on a very steep incline. Even with the wrist pad that's included, it put my fingers in a big strain to operate the ball (I have average sized hands). It's tilted up, so that you have to reach up and out to use the ball. This puts strain on the tendons of your whole hand, and also presses the nerve cluster at the base of your hand against the pad or table. After using it for about a week, my hand was in agony. Earlier Kensington Expert Mice were almost flat, and were very comfortable. It's baffling to me why they made this change in the design. Kensington did take this mouse back for a refund even though I had used it for a week (all I could stand). It may be that this unit is comfortable for someone with very large hands. I've gone back to my Logitech Marble Mouse, regretfully -- if not for the incline, the Kensington would have truly been the perfect trackball.