Does anyone know a good BMW Certified Technician

My 540i has a very rough idle and I am looking for a good BMW Shop, other then the dealers around the Newark, NJ airport area. Can anyone help?

there was a technical service bulletin for a certain timeframe of bmw 4.0 engines having a problem requiring engine replacement. if your car falls in this time period, i'd go raise hell at the dealers. if it doesn't, then your car has probably got either leaking intake gaskets, a leaking oil seperator, or a leaking throttle body gasket. its pretty extensive work. check the T.S.B's.