I used to like the R.A.T. 3 but after the 3rd one died I decided it was time for a change. I saw the Cougar 550M at Tom's Hardware page and decided to try it because I thought it looked cool. It is a very good mouse. Cougar is German company and the device feels solid, like a Mercedes.
I have only had the mouse a few months and tonight I thought it was dying. I went to Micro Center and picked up a cheap Gigabyte M6880X as a spare. But the spare didn't work any better either. I thought it was my USB hub and I threw it away (D'oh!).
I just discovered that I wore out my mousepad! That has never happened before. I love using the 3M Precision Mousing Surface. @JokerProductions tested it last year in a video vs. the TS mousepad. the 3M PMS is a thin cardboard Post-it with a bumpy plastic surface on top. The plastic is very slippery and the bumbs are micro lenses to reflect the sensing laser of the mouse. 3M claims that their tech will increase the life of wireless mice. Anyway, I just noticed that I have been using the mouse so hard that I wore the bumps off and the mousepad is smooth plastic in the middle.
Good thing it only costs $8 (+ the $20 USB hub I threw away + the Gigabyte mouse I don't need).