Nice vids! I'm from Luxemburg, so german highways are not far away for me!
You're absolutely right, that the hood moves a lot, while driving over +200 kph! My former Subaru WRX had the same problem, at 200 kph!
I drove to Munich, 2 weeks ago, and after hundreds of km and some hours on the Autobahn, my stock exhaust was louder, in comparison when i only drive 50 km a day here at home!