I have not read all the posts; I am lurking here to learn more about the F01, I will be selling my '08 E66 in May 2014 and will likely move to an '11 F01 or '11 XJ8.
Anyhoo, has anyone tried "on the car balancing" of the wheels. I had a chronic issue with my 87 300E and a guy whose Alfa Milano Verde I was test driving told me about the same problem and "on the car balancing" solved his vibration. It balances the wheel, tire, rotor, hub, bearings, i.e. and rotatinal component relative to the wheel. I never had another problem and did not rotate ever again once the balance was perfect on my E. Rotation was not necessary with the 3.0 putting out only 177hp and 188ft.lb to the rear wheels.
On the car balancing will NOT solve a defective component like a driveshaft, U jount, etc.
2008 750 Li Alpine White/Creme
The economy will get worse before it gets worse.