Regardless of which performs better, I've gotta say any vintage race-car is WAY cooler to me than any comparable modern street car.
Give me the opportunity to drive a road course in either the Penske/Donahue Camaro or The Mule, and I'll pick the Penske/Donahue car.
Give me the opportunity to make a pass in either an authentic straight-axle'd '41 willys that runs 10s, or some pro-streeter that runs 8s, and I'll pick the willys.
Give me the opportunity to go around Daytona in Smokey Yunick's '66 Chevelle or Dale Jr.'s modern cup car, and I'll take the Chevelle.
That's why I'm building a PT car, instead of buying a 'vette.