It's AMAZING how much this mouse is better than others out there. It is incredibly comfortable in your hand. Without that darn wire tugging at you when you move the mouse, the stress on your hand is much, much less. You can even use your mouse on a side tray, or on a lap-tray or anything else. You could vary your position daily to keep your wrist in shape.
I had heard from some people that cordless mice had slow response time - but I use this for everything from design work to word processing to database development to serious gaming, and it's never let me down.
I recommend this to every computer person I know. It's really, really great!