Do yourself a favor and buy some higher quality servos, I like the Hitecs for my higher performance small planes.. the $2 servos will continue to frustrate you, hate to break a plane because one just decides to stop working all together, they are cheap for a reason.

how are you "Powering up" the ESC if you're not plugging in the battery?? the ESC has a switch I guess,, I never use those,, I leave them in the on position and plug the battery in when I'm ready to fly. I've never trusted those switchs since my RC car days, they always seam to fail one way or another,, some I've had to cut off and solder the wires together,, they never failed then.

good luck