The part that is getting beefed up is the rod-ends since they had a 150 revo get reported for that problem. Plus from the site that is the only thing people have been complaining about. Besides the fact that the 2.5R isn't easy to tune, and people not being able to shift to second gear. But I don't care what the problem is I just can't wait to get one. I have seen some run at my lhs track but that's about it. And the two guys that have them went to Ga to get them. If I wasn't so loyal to my lhs I would have done the same. Anyway's that's the scope on the revo and upgrading part(s).