I've got the MMO 7 by Madcatz. So far, I've liked it. It's big and ergonomic enough to be comfortable. I can't vouch too much though for the keybinds on that thing. Mostly because after 10 months here in game, I'm still experimenting with it. I have noticed that I'll get where the cursor drifts on it's own a little bit, but I'm not entirely sure that is a problem specific with that mouse or some other factor.
Other than that, I've been pretty satisfied with it. But I still consider myself to be pretty noob to the game (and MMOs in general). So, grain of salt, and all that...