Sure the ZR-1 might be faster on the track, but when people see a Vette on the road, it barely gets the kind of attention the Viper does. So unless you bought a Viper and ONLY drove it on the track, then all these lap times, skid pad performance figures, etc are kinda moot. Buying the car to enjoy it on the road, as long as it makes you happy and enjoy it, that's all that matters.
If you were planning on just racing it, well then I can't help you there, lol. Corvette has had a bit more practice in that regard.