I've owned two Audi A6s.
I only owned them for two and three years respectively, but to be fair, I never had any issues with them.
I've had five Mercedes E Class over the last 14 years or so, no problem with any of them either (bar an annoying occasional rattly buzz from the dashboard in my current car).
Looking to downsize now, but not too much. Lexus had a few things going for it when I started looking; cost (a lot cheaper lease-wise than the Audi, BMW or Mercedes alternatives), it's still a quality marque to my mind and the Audi Q5 is such a bland, boring looking car to me.
I've never had an SUV type car before, but after the test drive I am very much looking forward to having one in 6 months time (fingers crossed).