If it were me I would avoid painting at all costs. I hear that the NSX had a nice 24 step paint process from the factory, I wouldn't want to take this away for anything.
Good luck finding one with all original factory paint on all panels, bumpers and roof. Usually some part of the car eventually will get re-painted after 5-10+ years. However, it's not impossible.
I never liked White cars period. It just looks too plain for a sports car. However, the true NSX-R type is one I wouldn't mind having.