Hands down, Braman West Palm Beach. I live in Miami, too and drive the 60 miles each way just because of the service. Braman Miami is a circus. They are simply awful. Try WPB once and you will never go to another dealer again. Jose Ortega is my SA (Service Advisor). He's the bomb. Chris Huffman is the Service Director. He will greet you by name and make sure you are 100% satisfied. I've had three M3's (E46/E46/E92) and 5 other BMWs. I have to say, I consider myself a dealer expert.
Good luck.