The stock motor might well be ok, we won't know until they've had a few good runs, although I don't like the cheap looking heatsink they've fitted.
Yes i very much agree, it's early days yet an its probably a castle can anyways !
Someone made a comment that I thought was spot on , Traxxas seem to have known it needed that heatsink from the outset , I'm sure if they could of saved a few $$$ by not having to fit it they would of , and may that be the reason for the plastic motor mount , maybe the heatsink blew the budget lol .