the four stars are extremely light airplanes that will float forever. the recommended engine is plenty for it, i would suggest an OS fx. i have a four star 40 with an OS .46fx. wonderful airplane. rock solid will do most moves smoothly(knife edges are really nice). a friend from my club has the 4star 60 with a tt 60. the engine gave him a bit of trouble(plane glides nice even on a deadstick) but the plane still performs well with the combo when the engine decides to run. also, i don't know for sure about the 60 size, but the 40 size tends to have some aileron flutter at full speed with the 46, mine doesn't show it yet, but I have seen two with flutter problems. wasn'e real violent, but causes some concern.