i like those GTOs as well, but i personally wouldn't get one, i would rather get a C5 than a goat.
i htink the best bang for the buck, and you will have plenty of it left t stick a twin turbo in, is a late model LS1 camaro or trans am, those things are so cheap to mod and there are a lot of them out there to choose from.
just go to ls1tech.com and check it out for youself.
the only car so far that ever made me wanna go puke and made my stomach hurt was a lingenfelter camaro, no joke that was by far the scariest car i ever been in.