The current issue of the German "Autozeitung" compares new cayenne turbo with ML63AMG. The results:

Cayenne / ML63
0-100 kph 5.2 / 5.1 seconds.
0-180 kph 15.1 / 14.2 seconds.
Test consumption 23.5 / 18, 9 (l/100km)
Brakingdistance (100 kph-0 kph) coldly 37.8 / 36.9 m
The ML 63 wins the test and achieved place 1.