This topic has some cross-polination form another on here; for me I wouldn't ever spend extra $$$ on a premium sound system in a car. For me it's largely radio & a 'decent' system is good enough.

I don't want to be distracted by listening out for the 3rd violin when I'm in a car; I have other things to do.

Cinema: Meridian 271, 3 x DSP640 (behind screen), 4 x DSP320 (in-ceiling), 4 x DSP3100 (surrounds), 2 x AC12 (interface). 2 x Perlisten D12s subs, Lyngdorf MP40 processor. DT 145" 2.35 AT screen. Sony VW870 projector & S-T lens, Lumagen Radiance Pro.
Lounge: Roon, NUC, Kef LS50 Wireless + 2 x REL Gibraltar-2 subs

Meridian owner since 1998