Autozeitung Magazine just published this test where the GT-R comes out on top . The new direct injection Porsche 911 TT is faster in a straight line, the GT-R is faster on the track. The GT-R is running the Dunlop tires, which are quicker than the Bridgestones. The P car guys will continue to hate on the GT-R. Cheaper, faster, and easier to drive. I am not sure when easier to drive fast became an issue rather than a compliment.
GTR vs 997.2 Turbo Track - 1:36.5 vs 1:36.9 18m Slalom - 69.8kph vs 68.8kph Braking for 100kph (cold) - 34.2m vs 34.9m Braking from 100kph (warm) - 32.9m vs 33.4m
Source : 6 Speed Online Forums