The Sidewinder is rated to handle 3s, but is 4s capable with a BEC.
but only with a small motor (which is what is being used in this application, so it would work).
in the traxxas video, the mini erevo does a standing backflip. if that isn't enough, i don't know what is.
They say a good mechanic only needs 2 tools - WD40 & Duct tape. If it moves, and its not supposed to, duct tape. If it doesn't move, and its supposed to, WD40.