you also could pick up a hobbywing Brushless ESC/motor combo a 60A one is about $100 shipped
Put a 8.5T BL ESC/motor combo in my Brama 10b and snapped its rear end off after 5 mins (HPI made the Brama out of REALLY low grade plastic) and destroyed one of the diff gears(that too had plastic which broke...). Stampede should be able to handel it though seeing it was made to run the VXL brushless setup
But for the 5 mins it ran before having a chassis failure it ran faster than hell