Try a 9X3.8 APC slowflyer prop. We have been using them for several months with very good results. A couple of days ago we tried a 10X3.8 on my sons Reflection and while it added a noticable amount of thrust in manuevers like a funnal, it also caused an excessive amount of torque in a hover and some other manuevers. It took three times for my son to drop into a hover because the airplane would torque completly around with the application of power until he started using large amounts of aileron to hold it. With more practice that evening he said he was able to get the timing down to drop it straight into a hover ever time, but the excessive torque was still causing funnys in other manuevers. When he got done flying the Rimfire motor was very hot to the touch, something that never happens with an 9X 3.8 prop. We are in the process of cutting the 10X3.8 down a little at time to see if we can find a balance between more thrust and less load on the motor. If we aren't sucessful, we abandon the 10 inch prop and go back to the 9 inch props.