I already bought the mouse today. It's a wireless Logitech Marathon. I try to get ones that are most comfortable in my hand.
I'm trying to protect my hand and wrist from future problems. I use a comfortable mouse, padded wrist rests for the mouse and keyboard, and for warmth I wear a fingerless crocheted glove on my mouse hand (sometimes both hands; I make them myself in various colors).
I did look at the gaming mice while I was shopping. They sure do look cool. 
