For me and considering all models
Fit/Finish
Lexus
Acura
Infiniti
BMW
Never owned a Mercedes or Range Rover. Range Rovers have pretty horrible reliability ratings but I love their interiors. Some of the nicest leather.
My Infiniti has a lot more stuff but if I kept it for 100k miles I would expect Acura/Lexus to hold up better. We have friends with a 10 year old Honda Pilot that has 150k miles that looks brand new and not one squeak.
Bang for the Buck
Infiniti-They live and die by one model which they got right, the G37 sedan. Two good SUV's. Everything else is kind of blah.
Acura-Acura is doing it right with their SUV's but their sedans are just not competitive.
Lexus-GS is nice, new IS 350 is nice.
Mercedes
BMW-Always about 20% overpriced compared to Japanese. Their best models seem to be the cheapest models (1,2,3,and 4 series). M series are wonderful but again way overpriced IMO
Most boring
Lexus (Except the F models)
Acura
Infiniti
The brand that is finally getting it right seems to be Cadillac. Nearly bought a used CTS-V but the interior still seemed pretty junky for that level of car. I was impressed by the ATS that I sat in though. The big 3 have been nailing it on their powertrains for a number of years but some still have some work to do when it comes to interior quality in the luxury market.
One of the best cars I owned was
1997 Lexus ES 300 140k mileage
Traded it in for (one of the worst cars I ever owned) -a 2002 Lexus ES350-kept it less than one year. (Trans sluggish.)
Bought 2004 G35 Infinity -one of the best cars I owned 135k mileage.
Traded it for a 2013 G37 (One of the worst cars I have owned.) (Trans sluggish/noisy).
IMO, Brands change key components/designs as cost savings, and they are not as good as the originals. I do not like the move to 7 and 8 trans gears-- For in town 20-50 mph driving, constantly changing gears. I used to think the 2004 G35 was a sporty car, now the G37 is comfy, but clunky.
My wife has a Mazda 3 hatchback-it is a FUN car to drive-smooth trans, quiet, drives like a go cart. I am 6'2, I see a lotta comments here that tall people are wanting big cars,,not me.