My 2 closest friends both have Vipers. One is a 96 GTS and the other is a 96 RT10. I've driven both cars on many occasions including the drag strip. The GTS will easily run 12.20's with a good driver in stock trim with stock rubber. Add a few simple mods and it don't take much to break into the 11's.
As far as reliability goes, both have been very good cars, especially the RT10 which gets flogged almost daily. I easily could have bought a Viper when I started looking for the NSX, but what I really like about the NSX is that you just don't see many. Vipers are becoming almost a daily thing. With all respect however, the Viper is certainly one awsome machine. It's so different than anything I've ever driven or owned. Damn fast with even a novice driver. The NSX is just a much more refined car. You can relax when you sit behind the wheel in the NSX, but the Viper is rather crude by comparison when your behind the wheel. But I love that muscular feel of the Viper. I sometimes wish I would have gotten the Viper instead, but than again if I want to release some aggression, I just drive the ZR-1 for a couple of hours. It's almost as quick as the Viper RT10. I've run 12.60's in the ZR-1.
I just love cars in gerneral and find many to be quite enjoyable. You don't have to knock Vettes, Vipers, or any other make to make yourself feel better about the NSX. Someone will always have a bigger and better #$%!#@% no matter what you prefer to drive. I like to give anyone a wave if they are driving a special interest automobile, be it a Ford, Dodge, Chevy, etc, whatever. I've learned to appreciate a little bit of everything.
i guess this is what happens when boys buy men's cars. But seriously, those kind of video's start flame wars... (not ur fault) so i hope nobody here starts a z06 flame war... or the troll patrol will rip them a new one. 
