I've been using these mice on different computers for several years. While I recently upgraded to a Kensington Expert, I still use these logitech mice on my other computers. These logitech mice have a great feel, and once you get used to the trackball it becomes nearly impossible to go back to the handheld mice. Not only do these mice feel more accurate, they are also much more comfortable for the wrist! I never have any wrist pain, unlike when I'm forced to use a traditional mouse. Really, I have nothing but good things to say about this mice, but since I do not want to seem like a fanboy, I will throw out a couple of negatives: First, these are becoming very hard to find. Second, these things collect grub and dust underneath the trackball. This requires cleaning every week or so in order to keep the ball rolling smoothly and accurately. I'd suggest this to anyone who has wrist pain or who wants an accurate mouse!