The Logitech G5 and G7 are overrated. Try to go for wired mice, unless you really can't stand the wires. The Logitech MX518 or Razer Diamondback are perfectly fine optical mice. 1600 dpi is all you really need.
Yeah, I love my little (well, it isn't that small, but whatever) MX518. It's nice. I also have a WowPad mouse pad that works pretty durn well. My dad gave it to me because he didn't need it anymore. I like it.