Not an E55, but a slightly modified SL55 with ~550bhp and 600lb vs. a standard 2008 997 turbo tiptronic with sports-chrono is a very close race...
I was disappointed somewhat that the 911 was very slowly walking away from the SL, and continuing to do so well into scary numbers.
A similarly tuned E55 may take the 911 as it's lighter. I used to own a (standard) E55 a few years ago and replaced it with the 911 and the 911 doesn't feel any faster, but I'm sure it is.
Any of the turbos from the 997 Turbo S onwards (they got the far faster shifting PDK instead of my Getrag 5 speed auto incidentally shared with the 55k cars).
I must admit some of the funniest driving moments I had was from when I surprised people in 911's and Ferrari's in my E55 - the look on the faces when a big exec saloon kept up/out accelerated them was priceless.