Nice old car but there's the thing, it's old and people are prepared to make allowances for that. At track days the standard E30 M3's are pretty slow. The engine sounds nasty as well, gruff and rattly... BUT it is a motorsport legend and people pay big money for them now.
Just when does a car make the jump from just another old model that can't cut it against the modern stuff to collectable modern classic? E30 M3's have made it, as have Audi quattro's (UR), Porsche 964/993, Ferrari 328 and a few others.
Judging by the age of those cars the NSX should be on the cusp but maybe the relative newness of the last cars is actually holding them back?
Personally I love the E46 M3. Properly quick, handy size, great soundtrack even has a few luxury's. I'll take a run out CS model (CSL steering rack and brakes) with a manual g'box in Imola Red
Cheers
Mark