the OS 120 AX sounds great. Well, I flew my first flight with the OS 120 Supercharger and it flew great. the wind was strong yet it flew right through it as if there was no wind at all. VERY VERY STRONG. Idles great and the engine starts right away without hesitation. I have no regrets buying this engine :-D. There was one thing that went wrong though. The wind was strong and the engine was so powerful that one of the ailerons ripped out O_O. I landed it safely with one aileron attached. This shows how powerful the engine was haha.