Being in charge of IT purchases at work means I get to order all the office mice. Over the years I have used this to buy and try pretty much every top gaming mice on the market. I typically use a mouse for 6 months before someone else's mouse dies, and they get mine as a replacement. At which point I order the latest and greatest for myself.
Although the Logitechs generally score quite well, the conclusion I have come to is that if your mouse has the word 'Razer' on it, it's going to be pretty much the best thing out there