I remember a few things about the NSX v. 348 when both cars were new.
Car and Driver did a supercar comparison in 1990. If I recall correctly, the order (last to first) was Lotus Esprit Turbo, 348, Corvette, 911 C4 and NSX. (I am sure about the NSX being first and the C4 second).
I also recall that the 348 was described as absolutely horrible to drive at speed, and that one of the magazines (R&T or C&D) said that they almost aborted their top speed run with the 348, for the first time in magazine history, because of the poor stablity of the car over 100 or 120 mph.
The market apparently agrees, as 348 prices have dropped so low that they are at or in some cases below the price of a nice 328, which IMHO is a much better looking car.
Another Ferrari that has dropped like a rock is the Testarossa. They have now gone to the low $60k range, with some being sold in the upper $50k range. 
If I had to have a modern prancing horse and couldn't spend more than $60k, I would buy a 328 or save up for a 355. I would not buy a Ferrari unless I could afford a 360 Modena, and even then I would probably pass for reasons of personal taste.
YMMV. 
