Cruise control part number

Seems like BD would be ok for the saloon, with fuel computer, and you would need BK for the avant.
Note that the switches are a single block, you cannot easily mix and match modules from your old set and the new set.
(Echoes of lesson learnt the hard way...)

I fitted BD to my 08 Saloon with 9Q4...it works fine but there is an additional code change in VCDS required in addition to programming the cruise control in.

If you Adaptive Cruise or Lane Departure then you need a different part number. As above Avant is different as well.

If you wanted main beam to stay on the stalk would lock when pushed away from you. The BD stalk however doesn't and springs back. A quick change on the Central Electric module will sort this though.