I had bmw's before maserati and had a few insurance claims. When it was a NON FAULT I used bristol and london as a claims handling agent. They were faultless, A equivalent car (infact upgrade 330d) within 3 hours, to my workplace, all details were completed by them and all costs recovered form 3rd party. for FAULT for which I had one claim - hit a deer at 50mph - I had a bmw assist car for 48 hours and then the garage let me a car whilst they were fixing mine.
For both accidents I asked them to use BMW workshop to keep my warranty and they obliged once they had researched it. It wasn't the garage they wanted to send me to or on their original list but they allowed it - not sure of the specifics. The work could not be warranted by the insurer, this was the only catch, but specialist cars bmw warranted all their work anyway so it wasn't a problem.
3 BMWs and 5 claims in 3 years
!!!!
*awful spellings its late