Man,
I have got a wired rollerball mouse that I absolutely love. The ones I have used are the logitech models with the huge rollerball. My hand fits just right on the thing and it doesn't have to be wireless because it is stationary on my desk. For gaming I prefer the roller ball in a game like Unreal for the shear mobility of a stationary ball over a mouse.
So for me it's the rollerball all the way...