Of course the Skymaster has the advantage of no motor torque or asymmetric thrust with an engine out, both useful attributes in a model.
My scratch built 52" foam job (actually an O-2 'special ops' variant) flew extremely well with masses and masses of spare power.
View attachment 154990
Hand launch and belly land (which that fuselage did very nicely on grass) with just 'bank and yank' controls.
A throttle mix allows the front motor to be switched off in flight. Like that and flown super economically it had an endurance of 3/4 hour on its 2200 mAh 3s.