This is a question we get quite frequently since we offer both our supercharger system and our twin turbocharger system for the NSX.
The determining factor is in general the power goal of the customer. The feel of our supercharger system is like you took out the factory engine and put in a 450 hp small block V8. The twin turbocharger system provides smooth power delivery thanks to the twin setup with power delivery that can be anywhere from tame to warp speed.
In general, our supercharger system is better for the customer who wants a forced induction system that will produce around 400-450 hp at the crank, wants instant boost response, does not plan on modifying his stock engine, and wants a system that is somewhat easier to install (takes approximately 14 hrs). The system is very quiet compared to any other supercharger system available.
Our twin turbocharger system is more ideal for the customer who may have plans to modify the engine down the road (the system produces 450 hp at the crank on a factory engine, and is capable of producing nearly 900 hp with engine modification), and is willing to spend a little more on installation (takes approximately 20 hrs. The system is fairly quiet, thanks to the twin internal wastegates, with just a little turbocharger sound (blow off valve, etc.)
Both systems are 100% reversible, requiring no permanent modification to the car, have a long track record of reliability, offer the highest quality best design system whether you choose supercharger or turbocharger and include everything you need, down to the finest detail.
You can find lots of information on our website under "supercharger & turbochargers".
-- Chris