I've been playing counter-strike for the past 7 years and have had the pleasure of using the logitech mx310, 510, 518 and microsoft 3.0. I'd have to say that logitech makes great quality mice and have amazing customer support. The mice feel really solid and well built in your hands, and when they do break, logitech has a pretty much no questions asked 3-5yr warranty (I can't remember how long it is) and they'll send you a new replacement mouse.
I have fairly long fingers, so eventually I made the switch to the microsoft 3.0. It's build quality isn't anywhere near logitech's offerings, but its design is much better suited for my long fingers and low sensitivity play style. With the 518/510 I'd often accidentally hit the right click button when I moved my mouse quickly during "quick-reaction" moments. I don't have that problem with the 3.0. The big downside to the 3.0 is that one of my side buttons and the scroll wheel broke after the 2nd year I had it, and microsoft doesn't have the great customer support that logitech has. I've just gotten back into counter-strike after taking a year to focus intensely on school to get into the colleges that I desired, and have bought a new microsoft 3.0. It's build quality seems a bit better than my last one, but still not up to logitech's standards. I thought about picking up a deathadder since it is based on the 3.0's shell case, but decided to just stick with what I was familiar with.
btw for those of you who play games with low sensitivity I'd highly recommend a steelpad qck series mousepad. They are really slick and durable for cloth pads.