I built a Stuntman 23 with a Fox 09 and it flew adequately but not spectacularly for lack of 09 type power. I had at least 2 of the pet 09's when I was young and they were new engines. They are not powerhouses and can be difficult to start at times but I enjoyed them. Why not, I was young enough to enjoy just about everything about models. make sure that you use a fuel with enough oil in them or they will overheat.