For a high quality US option, you can't go wrong with castle creation's new 1406 series motors for 1/10 buggies and trucks. They are greatly improved from the older castle motors and should perform on par with the high-end german motors.
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.