My buddie has an RCGF 50 and it runs great. I personaly would stick to glow on the 25% unless you dont care about 3d type stuff at all. An OS 1.6 would fly the crap outa that thing. I originaly had a evolution 26gt2 on my wildhare 25% and it flew ok but was lacking pullout power. The tuned pipe would of helped get it to a more reasonable amount of power but I didnt want to mess with a pipe on a plane that wasnt made for one. I switched to the OS and it flew the crap out of it. The 25% is a tough size to go gas with great results. The biggest problem is the 26cc are just a bit to weak but the 35cc are usualy as heavy as a 45cc so there is no great fit engine esp now that the 26ssr is gone. Someone needs to make a 30cc that weighs as much as the 26cc but makes 18-20lbs of thrust. I wasted a good amount of money trying to get a decent 25% gasser and personaly came to the conclusion that if I want gas on my aerobats it has to be 50cc or bigger.