I like driving something one seldom sees. Vettes are common, Vipers are fairly common, stock early Z's are less common, and nicely done customized widebody early Z's are rare. Personally, I like the 250 GTO's because they're very distinctive and most people have never seen one. Nice widebody Z's are nearly this rare too. I don't know why but I just like getting a rise out of people. Vette's and Vipers do that too but, IMHO, they're comparitively blas'e.
I think you should be able to build it for way less than $30K though... unless you're paying a professional garage to do all the work and you're expecting perfection.