Summary: I paid just $7 for this after the $10 rebate, so I'm looking at it from that perspective. Just keep that in mind.
Pros: Low price, cool blue LED, nice feel.
Cons: Whenever the mouse loses power (i.e., the PC is shut down), it resets itself to the lowest DPI setting. This is very minor though, I just push the DPI button twice after it boots, because I like it on high.