I had this with my M3, got a top tip for you all.
If you ever go through the insurance company and its not your fault, use accident exchange.
I did this as I was not sure the guy was going to admit to it, so they took control and delt with his insurance, after a quick chat he admit it.
They said I could take my car to any spray shop I wanted.
They then called back and told me I would be getting a BMW 330Ci Convertible M Sport E90! Brand Spanking New!!! The toys it had just made me fall in love, but was good to get the M power back again.
Anyway, cant fault this service, I signed one piece of paper, thats it, had a online portal to show how things are going etc.
I know this is only a small dent but in future if anyone does have a smash, use them.
PS I had someone do this to my Old RS Turbo, right on the back corner, they new admitited it and before I could take photos etc the car was gone and repaired and I didnt have a leg to stand on!