Do you put as much effort into your Car Audio?

Not as much effor, but a LOT of effort nonetheless. That effort comes in the way of paying for a nice car with a nice OEM system. In making my purchasing decision, I put a lot of weight on how the system sounded and the noise level of the cabin when the car is operating.

I do wonder about how difficult it is to integrate a non-OEM audio system into a modern vehicle given the complex electronics and displays. Also, many modern cars have been pretty extensively engineered from the early design stage with the audio system in mind (even basic body structure is designed for specific speaker placement).

I would be reluctant to mess with the system built into my car. I also have some doubts about how much the sound can be improved given that noise is obviously the biggest limiting factor in sound quality in a car. My car is supposedly quiet (2011 E350), but, I really cannot hear the quieter passages of the classical music that I listen to almost exclusively when I drive.

If I had to pick the "best" sound I heard in a car, it would actually be such a custom, non-factory, installation I heard in an S500; this system utilized a vacuum tube amplifier (fortunately the trunk on this car is large).