I don’t have much experience in high-end luxury cars but I have owned a spectrum of brands from European,domestic and Japanese manufacturers.
Honestly I have never been impressed by a factory system. The H/K in our older Mercedes was a joke. We all know Bose is a gimmick. I’ve heard the Fender systems are pretty good but I’ve never had the chance to demo them.
The best I think I’ve heard is the Logic 7 in BMW.
What are some of your favorites?
Harmon Kardon in Saab is a good one. Not audiophile, but adequate!
Acura has had some nice systems too