I carry few others with my opinion, but I have to suggest staying away from optical mice for gaming.
After using optical mice for gaming and then going back to ball mice, the precision control you have with a ball is unrivalled with an optical mouse. Don't get me wrong, I know that everyone loves optical mice, especially for browsing Windows, but when it comes to gaming, a ball mouse can't be beat if ya ask me.
If you are dead-set on getting an optical mouse, I've heard really, really good things about the intelliMouse.
-Lasereth