Well, I have seen quite a few people weigh in on this question so I thougt I may take a stab. I see that many here have owned/do own a Ferrari along with their NSX. I am just the opposite. I own neither nor have I ever owned one. Thus, I think I have unique perspective on this issue.
Just yesterday, my friends and I were on our way to Chilis to get some chicken fried steak, and we came upon none other than a late mode NSX. It was black with the seven spoke rims. I did not see it. One of my other non-car-buff friends pointed it excaiming that "that is a sweet car." I don't even think he knew what it was. I then explained to him that that was the car I was looking at to purchase...the Acura NSX. This was just yesterday!
I believe that my friends reaction to a Ferrari would have been no different.
The above example is what I feel the norm is. Most guys will have that reaction to any NSX or Ferrari. They will point and they will think it is good looking. Girls, however, are a different matter. Girls will not notice either a Ferrari or a NSX any more than they would a Corvette.
There are three cars that will have EVERYONE staring or pointing...small crowds gathering, etc....(that you could buy in the showroom new in the past twenty years)
Said cars are the Lamborghini Diablo(or countach), Dodge Viper, and the Hummer. These are the most outlandish cars on the road today. NOTHING else even remotely resembles them. They are no compromise type vehicles. I find it rather fitting that all three of them have the worst fuel mileage of every other car on the road.
Now, if your lifelong ambition is to own a car with the prancing horse on the hood, then buy the Ferrari. If you find that the Ferrari is not the joy you thought it was going to be, then you can always sell it. Perhaps you will want to drive your Ferrari more than it wants to be driven hehe.
If you are not sure of the information in the latter paragraph, then think of how you are going to use the car. If you want a car that you can drive daily, take to the track, take on trips, modify(without too much $$$,) then go with the NSX.
If you are going to put less than three thousand miles on your car a year and prefer the looks of the Ferrari(because you will be sitting the garage looking at it most of the time), then go with the Ferrari.
Sorry this post was long. I thought my perspective of not owning any of these cars may help a bit.
Now, let me put in some disclaimers here. Yes, it is true that I do not own any of these cars. Then again, why am I on this board? Could it be that I think the NSX is one of the most awesome looking cars and I think it is greatest GT car anyone can buy? I guess in reality I am extremely biased in favor of the NSX hehe.