Flying tiger,

I think that the little screamer motor should work out good. It sure seems to have a lot of power on 2 cells. I think that the reason I go for 2 cells is the weight savings. You will save 1/3 the batteries weight by going with 2 cells. I have begun to run the new hacker a20-34s all I can say is this motor has out preformed any motor I have ever tried. It flys the new shocky yak around with so much power. I am only running 2 cells on a 9x3.8 prop which gives it very slow horizontal speeds.
Bill,

I have been flying the F3A shocky and love it almost as much as the yak. I made a mod to get about 70 degrees of elevator and it is close to the same feeling as the yak. You will be able to 3d it great. It might not do waterfalls as tight but will do all of it. I think it flys better as it has no mix in it at all for precision maneuvers.

Andrew