Just thought I would share my perspective as a Porsche and Ferrari enthusiast on the early Vipers.
If you frequent the Rennlist or Ferrarichat boards you will see a lot of owners of very, very expensive exotics cite the early Vipers (GTS in particular) as some of their "must have" cars, keepers, or cars they intend to add in the future...
They are usually described along with 993 Porsches, classic Ferraris, and others. Comes up very often in threads about cars that are "keepers".
From my own very limited experience so far (96 GTS, completely stock, completely restored wear items, low mileage) is:
* The experience of driving the car is more of an event than almost any modern Porsche short of the GT2RS/GT3RS
* The aesthetics of the car are superior to almost anything out there (ages extremely well, along lines of Cobra etc)
* Lots of positive feedback vs. mixed or negative feedback in Ferraris, BMW, Porsche (not that this should matter)
* Significantly worse apparent build quality overall - really does not feel well constructed (interior) compared to other sports cars I have driven extensively (Porsche, BMW primarily)
* Mediocre exhaust note - though note I have a stock exhaust
* Mediocre steering feel - though that is in comparison to Porsche
* Loads of power and torque and incredibly raw feel - adds to the uniqueness and is maybe the American equivalent to a Ferrari F40 as the last of an era (and similar performance)
* Rarity more in line with the rarer modern Ferraris/Porsches rather than other cars at this price point
Overall it is a keeper for me. Not practical for my purpose to drive a whole lot, but I cannot imagine something more exciting as a weekend sports car. The only real letdown is the interior quality, though I must say it is really comfortable!