If you have the Setpoint driver control center thing open when playing FPS games the mouse will freeze randomly, most of the buttons will minimize you and it's just a pain in the arse, and the list goes on.

I think I spent about 45 minutes properly setting up my MX Rev and haven't touched it, let alone open the control panel thing since.

Ok i just got them both and i already love them!

I have to get used to the keyboard because its a little bit different than my previous one.
And the windows media player buttons are also very usefull.

The mouse fits perfectly in my hand and i love the fast scrolling thingy which you can enable with one button press.