Just got my 2019 Mini Cooper back from the Mini dealer in Ramsey NJ. The battery was running low and not charging properly (I was getting low battery messages on the screen), but fortunately it was replaced under warranty. Other than that the car has been fabulous.
The engine, transmission, windows, sunroof and the electrics work perfect. The exterior paint still looks like new and the run-flat tires seem hardly used after 12,000 New Jersey miles. Unlike some folks here, I happen to love the run-flats and have no issue with them. The interior looks like the day it left the showroom and has held up very well, the seats in particular look like nobody ever sat in them. These 3rd gen Minis use durable materials that seem to hold up very well over time. Overall. this is a great car.
Recently, I test drove a 2010 Porsche 911, and while the flat six engine is really cool, it still was not enough to make me trade in my little 3 cylinder Mini.

 

Looks great! Make sure you keep those headlights waxed and protected so they don't start to crack/fade from UV rays and eventually yellow.