 I've leased three BMW 550 series from 2012-2018.  The first two were pretty reliable although on one I had to have one of the injector port replaced.  In January of 2018 I leased the third, an M550i Xdrive.  It's nice looking, is pretty quick and it's fun to drive.  I took possession in the winter and around April I noticed the AC didn't cool...just blew hot air.  I took it in to the dealer who charged up the system and kept it for a week looking for leaks.  Didn't find any.  Car was returned and enjoyed great AC until late June.  Just today (June 24th) the AC went from cold air to cool and finally warm in less than an hour.  Now I have to make a long hot drive to bring the car back in to the dealer next week.  I get a loaner but it's an inferior model (except for the AC).  I've only had the car for 180 days but I'm already half way to officially being able to declare the vehicle a Lemon under Texas law.  Two other annoying things are the music connection and the wireless charging.  For music I mostly use Pandora through my iPhone X.  The connection to the car is unreliable and I generally have to restart my phone to get it to play.  I've used both the BMW app and Apple Car Play.  I definitely wouldn't recommend the $300 Car Play option.  The wireless charger is hit and miss as well.  I've used two phones that are Qi charger capable and both sometimes work in the car and sometimes don't.  They both charge perfectly on the wireless charger at home.   In summary the car drives well, but the AC and the electronics problems make the car a poor choice if you're a driver who wants his $90,000 car to work as advertised.  If you're wondering why I gave it two stars rather than one, it's because the AC problem doesn't matter in the winter.