When I installed my -2 arm I also installed +2+1 a-arms, the difference was night/day. Better handling, better acceleration, better balance in the air, just all around much better. I don't exactly know what my HP is, but it's far from stock, but not 85hp either. Granted, shee wheelies easier now...but still only when I want it to, it's not un-controllable at all. The only thing I can suggest is if you're 'iffy' about it, try & find someone brave enough to let you ride their's & make up your own opinion. I had never ridden one with a shortened arm before I installed mine and I have not regretted it at all. And I ride 90% dunes as of now. I'm going to be doing some MX also though. I have absolutely not one complaint, even when at the dunes. I can grab the holeshot like no other in the drags, shee hooks up well on both the dirt & sand, I'm running 20" 8 paddle strait cuts, similar to haulers but a little wider.