I don't keep any car past the warranty's expiration. We had too many clunkers in the past that died after the warranty expired. I couldn't afford that unexpected humongous bill. With MINI and the warranty coupled with the maintenance deal, we got out of the cars at 36,000 miles or so (two years approx). We kept getting excellent trade value for them so we have stuck with the brand. OTOH, I had a number of minor issues with Toyota and Chevy. Those problems usually resulted in the cars still being driveable, but required wasting valuable time and effort to get them repaired even when still under warranty.
It's really just a crap shoot I suppose. In my book, MINI has come up winners each time for us.
MINI less reliable than Porsche, Jaguar and Chrysler? I question whatever source you're citing.