I owned and nearly wore out 3 Comp Arf 3.3 Yaks, the servo installation instructions had you install phenolic arms on the stock plastic servo wheels and on all 14 servos. In 5 years of hammering these airplanes not even one stripped out; now they were ganged together mind you, 3 on each aileron, 2 on each elevator and 4 on the rudder. Just saying.

Bob