BMW vs MB Warranty

[jfmiii]

Looking at either a '16 X1 or '16 GLC300 for my wife. both similar in price. ive had both brands in the past, an '04 M3 and an '08 C350. My M3 was under warranty the entire time I had it and the only issue I had with it was when my SMG pump failed and the car was undriveable. BMW gave me a loaner and fixed it at no cost to me. The C350 I still have and have only owned it while out of warranty. It has been good for about $1500-2000 in maintenance a year. I have a great indy mechanic but am getting tired of dealing with my wife not having a car for 3-5 days, dealing with a rental, etc etc. Anyway, Ive heard anecdotally that BMW has gotten worse and MB better in the last 10 years in terms of reliability. Im not sure if that is true or not. BMW seems to have a better warranty from what Ive read and since this will be a car with a majority of its new car warranty still applied, that is plus. Anyone have any opinion on which is better in terms of reliability/cost of maintenance for a low mileage year old model? Any opinions on CPO for either brand? Thanks TRF!