Looking for independent AUDI service - London

[FCRS6 V10]

Hi guys RS6 V10 2009 ownere here with lots of recent service activity. Engine taken out to change small part underneath , bust coolant tube etc.

I am being moved from Victoria Audi in London to West London Audi. I have lots of issues with Audi service , especially the massive price tag for a London service. Any independent service companies you guys could recommend in London ? 

Thanks

Fred