I like the 'Vette as a street ******. Cheap, comfortable performance.
On the track (I go to VIR), I prefer Viper. Mainly because of reliability...but that torque! ach du lieber!
Pretty much all of my track buds who've had or have C5Zs have blown up their engines on the track. Not the stock ones (stock meaning bone stock or headers and air box stuff), but the ones who have done any internal mods at all. Even rockers. There's something about that LS-series engine that likes to go boom when mod'd. Mod'd street ones seem to be fine. Road course? Different story. LS-2 and LS-3s definitely the worst on track as far as reliability.
I've driven a C5Z on the road course. I liked it - it was competent. But something was missing...
My 2000 ACR (street legal) hasn't had an easy day in the seven years I've owned it (or the two+ years prior - previous owner tracked it). LOTS of weekend HPDE and TT use. One failure in all that time - power steering pulley. I don't think a Chevy could hold up like these Dodge tanks.
My last 'Vette I sold three months ago. 1996 C4 (LT1 car), 228,000 miles. Ran great! It was a fun street ******, even with an automatic. Easy to service and repair, and uber cheap. Bought for $3500, beat the hell out of it for a few months. Totally SUCKED on the track, of course (crappy suspension, and the Auto trans is horrible on a road course). Just killed time that weekend. But it didn't break. Also recently bought/sold a stock '99 Z28. It was faster than that '96 C4.
If I could have only one performance car, though, Viper all the way. Plus, I just feel cheap when I drive anything with a bowtie on it (sorry, Silverado sitting in the driveway...).