They are very different cars. I have both and have really enjoyed them. They are pretty different cars. The Cobra will usually have faster acceleration (which is saying something!) The Viper has much better handling and rock solid stablity at speeds over 100MPH. The Viper is a throwback to simple performance. Most people consider them to be pretty basic. 92s are the most basic. 93-95 are still raw. 96+ finally got door handles and windows. The tops leak on all of the roadsters and the tires are so big you still can't safely drive the RT or the GTS when it gets wet. Funny thing is, when I go from the Spec Racer to the Viper, the Viper almost feels civilized! Cranky is right though: no matter what you do to a Cobra it isn't going to be able to touch a Viper on the track. And a track-tuned Viper can only be beat by a factory-backed Vette. It is absolutely amazing what you can make a Viper do.
The Viper draws more attention, but the Cobra sounds *way* better. (Bob Lutz, former Chairman of Chrysler, once noted that was his big disappointment in the car.) Either way, the Viper and Cobra are really popular!
As long as people are going to do the flame stuff, let me assure you that every car crowd has their own views and jealousies. The Viper crowd tends to be jealous of Lambos and Ferraris. The Vette crowd tends to be jealous of Vipers. Ferraris get jealous of Vipers and Moslers. Etc. I will say there aren't too may Viper owners jealous of Cobra replicas, but many are jealous of real Cobras.
Ironically, as for me, I think over the holidays I have decided to sell my Viper. I find that I don't drive it as often as the Spec Racer (and neither really gets driven on the street that often). I am very grateful for having had the Viper experience (and the Viper Nation is incredibly fun). If I hadn't had one, I would probably always lust for one.
What will I get next if I do sell? I dunno. I am thinking of a Ferrari 355 or maybe a vintage Aston-Martin D4. Why? Just for something different. Another experience in life.
As for web sites, there is really only one:
www.ViperClub.org It is, by far, the HQ for Viper nation!
Best wishes. Have fun. Ignore the flames.