I am using the same servos from my x50

hs 475 on alerions, elevator, throttle
.22 61oz in at 4.8v

hs635 on the rudder
.18 69oz in at 4.8

Even at 35oz i don't think it will be too much of a problem. A 91 4 stroke would not be as fun on this plane. Contact OMP and see what thye say.