Certainly some super examples of luxury cars being discussed here (even those that are quite sporty, because most are still well-equipped with luxury car amenities, etc).
Here's another slant on the topic, which is just the opposite. Or what makes a mediocre common car feel so mediocre. A retired relative was checking out our Mercedes C250 and asked a lot of questions about it and sat in it for about 10 minutes checking out the usual lux stuff (moonroof, nav, Harmon Kardon audio, power everything, a thick flat bottom steering wheel with lots of controls, sport seats with endless adjustments and memory, paddle shifters, etc.), so I was curious as to his interest in the car. He mentioned his wife's 2008ish Ford Focus and how every aspect of it felt so cheap, including the driving experience. He was definitely interested in upgrading to get the lux car experience (and feel) which I found interesting.