RE: servos for 30cc
Forgot to say that reason I went with ts-170's on everything except throttle on my gas 50cc plane is because of low wear titanium gears. I think for a 50cc plane, the ts-170's are a bit overkill and you might save battery power by going with less torquey servos. My servos pull around 3.5 to 4 amps max in flight. Other brands you might try are hyperions, seiko, smk, power hd digitals, etc.