I've got a Ripmax Trainer 40 with an OS 46AX. Its like they were made for each other. Plenty of power and loops are easy. You have to have almost full power and full down elevator for inverted flight though, but it's only a trainer! Flying it in wind is no problem and its a very sturdy plane so it will handle some bad landings. You have to back off to idle power on final approach otherwise you'll overshoot, but landings don't come around too often because its got a huge fuel tank. The C of G is bang on without any weight added to the nose or tail. One thing though is the pushrod that controls the nosegear likes to bend, so I'd consider beefing that up, and the nosegear itself will bend on heavy landings, but I fly from rough grass strips. All in all its a good plane, I'd recommend it