Using a Naga personally. Took a bit of getting used to, but now that I've passed the learning curve I don't think I could go back.
The Cata mouse may look pretty, and I looked at it at first, but product user reviews made me stay clear of it. Most common complaint was the size of it. It's really massive to be moving around on your desk constantly. To understand, take a fresh, unwrapped pack of notecards and try to move it around on your desk for an hour. Same feeling. On top of this, the durability is rather questionable. A friend of mine has the older version and I've personally seen it where all the paint/finish has worn off and half the buttons have stopped working.
Of course, this is just one case of thousands, but after researching I've found all these, and more, to be the top complaints. I'd advise to go with something else. ANYTHING else....
