Personally i think ANY car that can be had for UNDER 100K that runs UNDER 4 seconds 0-60 and 11.99 and under in the quarter is impressive and amazing.
5 years ago for those kind of specs you had to shell out between 250K to 500K for something that could obtain those numbers stock. Of course there's the, "well i could buy a used ls1 and make it run 11's for 20K yadda yadda"
That's not the point here, both the Z06, GTR, and i can't really think of another car under 100K right now, are impressive cars to do that feat.
Although i'd still shell out for a LP640 if i had the money