Only Fine Helis
50cc
I'm running the 5070's in my 48 extra and they work great. I would highly recommend them over the 65's.
I'm surprised nobody has chimed in with the Hitec HS5070:
http://hitecrcd.com/products/servos...ultra-torque-metal-gear-feather-servo/product
Designed for an (almost) drop in replacement to your HS65's, but with pretty close to double the torque. Perfect for 48" built up 3D airplanes.
You say almost... How much modifying is there?
I just ordered my first Extreme Flight 48" Extra 300 with the power combo. What discharge rate do you guys recommend for a 4S battery for this combo? is 70C too much?