Ford all the way for me, though the standard GT40 would be my preferance over both Premiums (in case you mean those).
Or just do what Mark suggests, back up your save and have fun in both before deciding.
Or save the money and get a lot of averagely priced cars from it, you could still get the cars from tickets, just sayin'. I appreciate that PD made those cars expensive so they are kept rare but I don't think they are worth 20 million each. Both together maybe.
