Mate, while there would be a tiny difference in lap time if you ran EXACTLY the same lap back to back (which is never going to happen) I'd say in a real world situation it wouldn't make much of a difference. That 1.5sec in the 33gtr (and I know who you are talking about ) would be down to the driver having more experience plus perhaps he was trying different suspn settings.
More of a consideration is cost of tyres, maximizing the track and what brake setup you can fit under the rim.