I have a OS .46FX on mine and it flies well. Good vertical, but not unlimited. For the type of flying I do the .46FX is well suited to this plane.

One thing I would caution you about is to reinforce/CA/Epoxy the landing gear plate better to the fuselage. Mine popped out after a harder than normal landing, so I repaired with a new plywood plate and tri stock. Works great now.

Everything else on the plane is completely stock and I have about 80 flights on it.