I also had a problem with the 605mg & 615mg servos, but mine were burning out. Hitec made good on them, but it was still a hassle. I switched to the digitals, and haven't had any problems. I've got 7 nitro r/cs using all Hitec equipment (actually 3 have Novak XXTRA receivers). I'm sure there might be better servos out there, but not for the money, and definetly not with the support you get from Hitec.