I've had the same one for 2-3 years. It's my first 'performance' mouse (I'm not a gamer), so while I don't have anything to compare it to, I would say that on pure functionality, with the Windows driver / settings interface, the customization options are nice and it performs ok (despite being generally overrated/overpriced).
That said, be warned that some reviewers (including me) note some units give off a high frequency whine at extremely low volume levels that's pretty nagging. It's one of those things that's (annoyingly) barely noticeable half the time, so not really enough of a reason to go through the RMA process, yet bad enough that after 20 or 30 minutes of sitting at your desk, you sometimes suddenly realize you're agitated and uncomfortable because the screeching from your mouse has quietly been chipping away at your sanity since sitting down. I've only avoided throwing it out the window so far because I regularly wear earplugs while I'm working/studying/sleeping/in-between-those-activities.
Also don't like the somewhat-stiffer chord, but that's pure preference.
Would generally suggest looking for something else -- e.g. wireless with a dedicated programmable macro matrix.
