Dave,
I may remove the differential once I get the thrust angle worked out. Rolls looked more like a barrel before the adjustment and I'm hoping the new thrust angle will help improve that.
My new radio equipment should start arriving today(Thurs) or Friday and I should be able to get the Intruder programmed quickly (I hope). The Aurora 9 is a sophisticated transmitter but, appears to be easy to program.

Speed and power has not been much of a problem for the Intruder. The Saito FA91 has mucho compression and pulls it very well through the maneuvers with a 13x7 or 13x8 prop. It has very good vertical performance.

I have a bit of a problem when doing stall turns the way you describe. If the airplane doesn't stop at the top at the turn, the judges take away points. So, I'm learning to hit the rudder switch for high rate to do the stall turn. It's been working for me as long as I remember to hit the switch before Ienter the maneuver. Sometimes Ineed a short burst of power to get her to swing the nose over at the top but, generally not. Having a fairly fast rudder servo helps I think.

RJ