I don't recall any real changes between the '11 and '12 on that model.
I've heard of a few broken reverse chains and a few bust front diff's........but most of those were guys running big tires.
One thing to check.....look at the engine side of the air intake to make sure that dust and dirt hasn't been getting sucked past the filter. I've seen that on a few, although I don't consider it to be a widespread problem. Mine doesn't have that issue.
PRCforum is the best Polaris forum community to discuss RZR 1000, Crew 900, PRC Ranger Club, XP 900, RZR XP 4 900, RZR 570, HD, 170, RZR-S, XP 900, RZR XP 4 900, ORV, side by side, SSW and off-road information.