Well, to answer one question. In the past no matter what BMW I purchased to save some cash and try to enjoy normalcy, I sold it and purchased an M product. I really hope that I'm at an age, 49, where I can simply appreciate a normal BMw. All too foten after reading another story of Sucky' Run Flats makes me only want to own another M product.
I have test driven the 550, and the 535, and both with the run flats transferred a terrible vibration thru the front seats. I actually asked my SA if he could see it and he said, "yes! I never noticed that before..." So from that day I started looking at Mercedes, Audi, Porsche, since they don't use Run flats. I like the feel but miss the excitement of the BMW product.
So, i am worried that I may have to go directly to an M6 to forgo all the rubbish run flats. Then my wife said why not just change the tires to non Run Flats. So, i wrote a letter to BMWNA and they said changing to non Run flats would void my warranty. So I asked my SA and he said it would not. Well, I need something in writing.
Then i thought maybe get the 650i Convertible. I mean it has the same horsepower as my old E39 M5 and it rides pretty good. So then I'm like, how about if the 640i has lots of torque down low and what neversummer78 says is true. We really don't need to go over 65 or so...
In my M5 I was never at 65...lol
Oh. just screw it and get this: