Serephucus wrote: » I've used the RAT9, and I didn't like it at all. It looks absolutely amazing, and the specs are great, but it's just not that comfortable. It's just very wide, meaning it doesn't lend itself well to being gripped. If you're a full palm user, then it might work, but if you're semi-palm, you might have trouble. I'm using the Performance MX at the moment. If you're looking for a comfortable palm mouse, with a nice thumb rest, look no further.