the elevators or ran by two servos and with out a computer radio it made it pretty hard to dial in. I'm still running the 91fx but changed to a 14x10 and had good luck with it so far it doesn't pull real hard or have alot of power but I think it's cause the plane has been repaired to much it's pretty heavy now and it's no light weight to start with.
I tried a 15x8 and it just didn't seam to fly fast enough to keep it good and steady with out being full throttle. the 14 inch i can fly around 1/3-1/2 pretty good and have some power for a climb, but it don't take long to peater out. the plane really needs a 120 or beter i think to get it up to a good performance level due to it's weight.
If your just building it don't fly it untill you reglue every seam you can, the first crash I had just bumped the front on the ground comming in for a landing and did alot of damage to it and most of the ply wood parts didn't even brake the just came apart.
I hope you have beter luck then I did, it's a beautiful plane to bad mine didn't fly as good as it looked[]