I haven't seen a pro gamer using RAT mouse so far. I had an opportunity to test RAT 9 for a few days, and unfortunately, it was a huge disappointment. While some people find it comfortable, I couldn't adjust it in a way that it had any chance to even compete with Razer Mamba or Logitech G700 in terms of comfort in palm/fingertip grip. For claw grip, it wasn't even close to G9x. Perhaps some Steelseries mice are even better in this regard, I haven't tried them. It was also very heavy, with questionable balance, and very difficult to lift off the pad (not to say that G700 can be lifted easily). I don't do that often, but it would make this mouse not an optimal option for a serious gamer. All that Tournament Edition sticker is just to sell it in my opinion, and not really use in any competitions. While I support what I have typed above, I don't mean that everyone needs a pro-level mouse, or that pro gamers need a great mouse. The most of the people will do fine with virtually any mouse in terms of precision, and if you play more games, just pick a better one that's comfortable. Pro gamers pretty much have to use what their team's sponsor is giving. So for example if they're sponsored by Razer, they'll probably use Deathadder (and not the most expensive mouse).