RE: U-can-do 40 with .46 FX doing the job?
I have a U-Can-Do .46, that at first I flew with a Magnum .46 two-stroke. It would haul the plane around the sky well, but when it came to tricks it wouldn't do anything real fancy, but would allow it to hang it. I currently have a .91 four-stroke on mine, which powers it nicely!
--Garret