Please do not take out your anger on the optical mouse by sitting on it, playing catch w/ it, handball, basketball, baseball, soccer, hacky sack, ect. Treat it well and you shall be rewarded w/ good operation in years to come. w/ that said, I've never had any problems you folks mentioned w/ the MX700, Cordless Optical that comes w/ the cordless keyboard, or any optical, cordless or wired. BTW, I never install the freaking software that comes w/ the mouse, ever.
The MX700 sucks up battery faster than the Cordless Optical, way faster. Using the same set of Ni-MH AAs, the former only lasted something like 50 hours (I stressed the mofo by not putting it back in the recharge craddle), while the latter lasted around 2 months.