RE: Cap 232 120 size
I have one with a Super Tiger G2300. Nice flying airplane. Mine had the funky pull/pull bellcrank elevator set-up. I removed it and went with 2 standard servos for the elevators.
Not sure if you're aware or not, but Airborne-models.com has one in their scratch and dent for $219 I think. Great value. World Models makes nice stuff. The Magnum should be fine for this model. Mine weighs just under 11 pounds.