Summary: This has traveled quite a bit with me for over 9 months and it is still working as if it were new. The little pads on the bottom have now all officially turned up missing, but doesn't seem to effect it.
Pros: Holds up wonderfully. Easy and solid retraction mechanism, or whatever you call it. Solid wiring, especially where the wire meets the mouse. Great sensitivity for casual use, and effective tool for most games.
Summary: I suggest you buy 2 of these right up front, because after one breaks and you have to RMA it, you'll need another one to use in the interim. Send the bad one by USPS First Class mail, that's the cheapest way. At least Belkin pays for return shipping. I've had to RMA 6 of these in an 18-month period.
Pros: Inexpensive. Lifetime warranty (you'll need it). End of pros.
Cons: Breaks easily. Very cheaply made. The cable coming directly out of the USB connector is the primary fault area. The scroll wheel is the second most cause of failure. These observations are based on over 18 months use of these mice in a home environment.