I have followed this thread with great interest and am dismayed that you were, in effect, driven away. I agree with the sentiment that you were ill-served by your dealer and then by higher BMW headquarters. My wife has had her 335 for a year and I have had my GT since mid-March and we have had no dealer issues at all. It is a first-class operation. I hope that continues.
Good luck with your Lexus and we will miss you on this forum once you have reached the end of your dealings with BMW.