The "I don't have control" situation is symptomatic of the on board BEC being overloaded.

E-Flite does tell everyone in their documentation that you are supposed to use NO MORE than TWO servos if you are using their ESC with 11.1v LiPo packs or above.

Yet many RTF or receiver ready planes come with 3 or 4 servos hooked up along with a 11.1v LiPo pack... or the pilots fail to head the warning on their own planes.

I've seen ESC's from other manufacturers used in a similiar manner, only to have the pilot loose their plane under similiar circumstances.

No one pays attention to the current rating of the on board BEC.... yet it is more important in most cases, than the ESC's power rating.