I like Logitech mice better overall, but the M$ drivers are a lot better in the sense that all of the freaking buttons work without having to bind to something stupid like Shift (a la MouseWare). If MS didn't have such a nice and courteous RMA system which is utilized quite often, they'd be a waste of money IMO. So for games I'd get a MSFT mouse (need those buttons working!) and otherwise get a Logitech (using a Logitech Dual Optical pimped out with one blue and one green LED BTW).