I have a Mad Catz R.A.T. 7, and it is an awesome mouse, but it is finicky as heck. If you buy one of their mice, go to their website and look up troubleshooting for it first thing, and follow the instructions, regardless of whether or not you appear to be having trouble.
Plug it into a USB2 port, not USB3, especially if your mainboard provides some kind of acceleration. Uncheck "Enhance pointer precision" in Windows. There is also an optimization program that is good to run. Currently my only problem is that it seems to pick up dirt over the optics easier than other mouse and requires a wipe with a clean cloth. I like it so much I hate to recommend against it, but on the other hand there are less finicky mice out there that also do a great job, just aren't as adjustable when it comes to fitting your hand.