Thanks for all the suggestions...to date, I have done several things. I've added 2mm shims to increase right thrust, balanced the plane until the CG is neutral which makes it fly straight and level right side up or inverted, and balanced the wings. I have also crossed the pull pull rudder slings as recommended in the manual (which I overlooked). Result? A better flying plane but still with tendencies to yaw left when hovering. Rudder input is better now, but it still doesn't respond as good as my Katana .46. Is there anything else that I'm missing out on?