Edmunds is notorious for slow acceleration times... I'm impressed with how close the S5 is to nipping on the RS4's heels...
If you want to triumph over time from a standing start, you dump the clutch at 4,500 rpm, sense a bit of wheelspin from the front tires followed by a stern kick from the rears, and 60 mph comes up in 4.9 seconds. You pass through the quarter-mile in 13.3 seconds at 104.6 mph. This compares to the 420-hp Audi RS4's 4.7-second acceleration to 60 mph and its quarter-mile pass of 13.2 seconds at 106.8 mph.
http://www.edmunds.com/insideline/do...hotopanel..1.*