I have a early model NSX and noticed that it makes pretty nice sound from the intake when I punch it. I can't tell if the exhaust make any sound at WOT?
Yes, the stock intake of NSX sounds great, if you like the stock intake sound you will absolutely love the intake sound with Cantrell AIS.
Stock exhaust is extremely quiet, it does make great sound, but you can't hear from inside the cabin unfortunately. If you stand outside and have someone drive it for you in a parking lot (not recommended, just an example), it sounds really nice.
Sounds like a dream, F355 has the nicest sounding exhaust IMHO.