Disagree. I have had the base car and the Z and the Z is a lot more car while being nearly as docile when you're not flogging it. IMO the OP does himself a disservice if he decides to go with a C6 and then gets the base car. Its a great car but I would never go back and other owners seem to agree, lots of people move on to a Z but few move back.
Not sure on the special part, in my mind there is no special C6 but if I had to put my finger on one I would go with the ZR1 if for nothing more than its the C6 with the mostest.
2012 E92 Space Grey with fox red/black/black, comp, premium, DCT, premium sound, sirius, heated seats.