It is quite funny really how people get blinded by brand, be it posh or less posh.
Often there are lots of subjectives at play here. There are few really bad cars these days, all will do a good job, work well, service a family and do the job for which they were built. Looks are totally subjective so not worthy of debate and the differences do come down to how you interact with your cars, how they drive and frankly often how they make you feel, another subjective.
I have mainly bought German cars over the years because for me they make the cars I like with the right balance of performance, aesthetics, reliability, driving feel, features and comfort. I remember joining an MG forum years and years back, can't remember why now, but so many there were absolutely adamant that their Rovers were better in every way than their German equivalents. They would not hear any negativity towards their beloved brand, blind to it's failings, clear in why their cars were just better. I heard many many times that you just buy cars like that to impress others. Their little world was all they knew and they all had a friend who's 3 Series was always in the garage and a wealthy friend who always bought Rovers and "he could buy any car he wanted". Sound familiar?
Lots of the debate was subjective of course, but for someone who had actually had both (I had Rover company cars more than once years back and as a loan car once) I could see it was rubbish. They did make a decent engine on occasion, they also did have some nice riding cars too but their interior quality and to me aesthetics were dire and their fun factor was lacking. They rattled, they felt tinny and we just not as good as a whole. My dad had an SD1 Vitesse back int he day, it was incredible but also terribly built.
So back on topic my order would be 5 Series, E Class, A6. I have driven all 3 of the current versions and that is where I sit. I think the E Class drives the worst but is a nice place to be (again a subjective). The A6 was a decent car and in many ways better than the E Class, with newer tech but I HATED the glass cockpit which is hard to work when driving and means a constant duster is needed to remove finger prints. But as always in this class, the 5 series is king. Best multipurpose saloon car on the planet since it's first day and I haven't changed that view since.