My family received several of these Logitech M-UV55A USB Wheel Optical Mice for Christmas. We had had trouble with ball mice in the past; the ball mechanism would cease to function, leaving the mouse unusable. The Logitech M-UV55A USB Optical Mouse solved all our problems and met all our needs. This basic mouse is not ergonomic, yet it still fits very nicely in my hand. It comes with Logitech MouseWare software, which is also downloadable from their website. The Logitech MouseWare software allows you to set up how the buttons and scroll wheel function, to select your pointers, the speed of the mouse, and also has Smart Move and Cursor Trail features. Smart Move causes the cursor to jump to the highlighted button of a new dialog box. This mouse is very sensitive, very durable and very fast. In all the time I have been using it, I have not had a single problem with it.