RE: H9 TWIST OR GP UCD?
I have a Thunder tiger Pro .46 on my twist, and it will fly straight up right out of my hand til i can barely see it, not sure about guys putting huge engines on this plane, how much vertical do you need?, most of my flying is done below 1/2 throttle, i find this plane to hover quite well and the .46 has plenty of power to pull it striaght up out of the hover.