Well see that's the thing, it's too theoretical. I mean, theoretically the enzo would out pace the c-gt but apparently did not at Nurburgring. And the .86 g for the McLaren, I somehow don't trust the fundemental importance fo that figure. The topics been brought up before at the McLaren section, and there has been refuted as meaningless for several reasons that I cannot remember.
So, I guess that this thread in the end is pointless (sorry) considering that all we can do is muse, unless someone out there has tested both around the same track (an interesting subject to research maybe...). Otherwise, yeah, it is pretty meaningless to guess. Oh well, maybe if we all got together, robbed some banks and bought both...