Basically, it makes easy work for the N54 based cars which are the BMW 335's and the 135i. The B5 S4 is running Tial 605 turbos pushing a healthy 25 psi of boost but it also falls back quickly. The only car that beats it although the run is very close is the turbocharged Mustang Cobra featuring a Precision 6766 turbo at 10 psi. The Cobra is the 4.6 liter V8 'Terminator' model that comes supercharged from the factory and debuted in 2003.
If we were to guess the E55 is said to be trapping 120 on the 20's inch rims although it looks stronger than that in the video. A bit more could probably be squeezed out of it considering some stock blower E55's have cracked 130 miles per hour (many with nitrous) but diminishing returns come quickly from pushing the stock 2.1 liter blower out of its efficiency range. To get more power, the Weistec 3.0 liter upgraded should be considered.
Regardless, this is a very healthy E55 AMG that runs strong. Thank you to @Urbamworm for the video.