After the "car chase" the white car gets put in the barn. When the black car arrives it is covered in mud (so much they have to wipe it off the windscreen) from the dirt track. The white car only has a few specks of dirt.
In the scene where Saffron is teaching Dougray how to dance at her favorite dance hall, there is a shot of some of the customers sitting and drinking. You'll see Mick Jagger talking to a girl at a table.