I have a 40 with a Saito 72 in it and it's a blast to fly. It's definitely overpowered (take-offs in 13 feet) but there's nothing that says you have to fly at full throttle. As for balancing, I didn't have to add any weight to the plane. I'll admit connecting the thottle control was a bit of a pain, but it was completely worth it. I do have one problem with the Four Star ARF however; it is difficult to see in the air. The problem could be easily fixed by making the top and bottoms of the wings have better contrast, but I have not done that yet. Good luck.