For the European customer...it's too big, too hot, too thirsty, too basic, too useless in our streets or as daily driver and too expensive due to taxes based on CO2....and apart from the last part, this is exactly why I like it.
Gas is way more expensive over here than in the states, which makes it for the normal man almost impossible to drive, not only due to gasprice, but also due to emission taxes, these taxes make the purchase price about double the US price and that makes insurance really expensive. The European magazines call the Viper a dinosaur, old fashioned, lumpy and brutal, to me that sounds appealing and I love the reactions on the car, but the market for such cars is very, very small over here. people tend to buy Porsches, Audi's or Nissans instead, they use less fuell, cost the same money, are more usable, people know the EU cars better and they can choose from a wide range of dealers and specced cars. On the Viper, allthough there are "lots" of options now, it does feel like take it as is for us EU customers...
Apart from all that, not too many people over here think the Viper is worth more money than the Vette, this one is more usable and the critics say it has better/ more EU spec handling and it's not as wild as the Viper..but than again, that's why I don't want the Vette.
On a Dutch board people tend to say that in the early days the Viper was worth the extra money because it was more faster...but now the old Z06 is about equally as fast as the current Viper...
To be honest I also went and have a look at a Z06, but it didn't steal my heart like the Viper does, mostly those floppy seats made that happen, as for the new Vette and the GEN 5 Viper exactly the same seems to be the case, the Stingray still hasn't got any nice seats and the looks of the car are way less aggressive than those of the Viper, I would still choose Viper, but many people choose the Vette due to usabillity and less screaming presence I guess...