Figured i'd chime in with my .02, my car club usually does drag race night once a month at the local strip, so far I myself, have raced 3 current generation mustang gt's, havent lost yet with my best win being a full second faster, probably a bad driver, but they were all pretty simple wins. I consider a full second "killing" to be honest, but like I said, he probably wasnt the best driver. If you want to have a numbers battle, the Z outperforms the GT from 0-60 Acceleration, 1/4 mile, Slalom, Skid pad, etc. Here is a vid for confirmation. If i'm not mistaken, that is a 2010 GT.
YouTube - Drag Race - Genesis Coupe, 370Z, Mustang GT
the article.
http://motortrend.automotive.com/104...onclusion.html
and if you're in for numbers..
http://motortrend.automotive.com/104...test-data.html