Hi together, would like to introduce myself here briefly: I am 47 years old, drive for about 4 years a 635 D convertible and think about buying an M 6. Built in 2013. Although I originally had a 640 D in view I have now torn back and forth. According to my research in the relevant sales platforms the M 6 or the 650 i is in similar, if not even lower price level as the 640 D. I would have to get a second vehicle because I have 50 km to work every day. How are the experiences here regarding the maintenance costs, susceptibility to the M6 or 650 i? I don’t want to start fundamental discussions, because I am aware that all 3 drivers are different. Many greetings and I look forward to your opinion/advice. PS: of course have the 635 D to sell.