I am going to purchase one of the GP gee bee arfs as soon as they come available. I am trying to figure out what engine to use though. I reall want this plane to haul *****. I like the sound of four strokes, thinking about a os fs 120, ys 1.40, or a saito 1.50 or 1.80. But will these engines make this plane really perform. Maybe an os 1.40 or 1.60 two stroke? I don't know maybe an rcs140. what engines do you think this plane go the fastest.