Independent Dealers?

[McP]

A friend is in the market for a Z3 (2.0 or 2.2 most likely). Having had a couple of Porsches I'm well versed in the main dealer vs independent (Camtune, Paragon, Autobahn etc) argument but know nothing about independent BMW dealers. Are there any out there and if so who would you recommend to buy from?

Is there a Z3 buyers guide available?

Thanks
McP