Best mouse ever.
I have a Performance MX now, only because I get a little bit of bluetooth lag with the old style longer dongles (haha) that ship with the Revs as opposed to the small nub dongle (..) that the new Logis have. I miss that side scrollwheel like a motherfucker.
If they finally started shipping the Rev with the upgraded dongles, I'm totally in the market. Best fuckin' mouse ever.