Gary my brother in law had a 2005 535 d a few years back, standard, it destroyed me from 60 mph onwards, I was in a very quick jdm WRX impreza
I definitely think for the top end speed scooby would flatten out and what u say is right Kieran. Had a BMW 530 one day up the arse pushing me up the road I moved over he done same but when off motor way it couldn't handle corners bit of a sloppy mess in rear view must of been weight of BMW but could of been the **** who was driving but the like a lot of German cars they are designed to do the motor way miles