[dparm]

I would think that a PPI at a dealer can check the number of times launch control was used. You need to work that into any negotiation -- they must allow a PPI at a dealer or you'll walk away from the sale.

As far as track usage, their weight causes two problems: overwhelming the brakes and overwhelming the front tires. I've seen lots of stock-ish GT-Rs roll up to HPDEs and end up in the gravel halfway through the first session because they boil the brake fluid. The weight also contributes to heavy understeer which chews up front tires in a single day. I think the understeer could be managed through better driver technique -- rather than just standing on the gas and letting the car try to correct your mistakes, focus more on minimizing understeer-inducing situations. I've never driven one on track, but these are the two complaints I hear most from owners at HPDEs.

It sounds like the aftermarket has largely stepped up to resolve these problems. If you're just driving it on the street, these issues probably won't matter.

I don't think you have to step up to a Porsche as "the next step" but I suppose it depends on what your priorities are. If you want a GT-R because you think it's cool, then do it. You haven't said that you're chasing lap times in time attack or whatever, so who cares if a GT-R isn't a perfect track car from the factory? For most of us, these purchases are highly subjective. We buy what is fun and gives us a good feeling. We aren't buying solely because of a lap time or acceleration number.