Do you put as much effort into your Car Audio?

Stock, it's good enough for NPR which is 98% of what I listen to in the car.

I prefer concentrating on the road, not the music when I'm moving down the highway.

No. Too much outside noise, inferior source quality except for CDs, too distracting for the driver, inhibition from playing realistically loudly (personally, I would be embarrassed to be playing loudly enough to disturb other drivers), cost I would rather save for my home system, and exposure to theft or damage from accident.

OEM has been fine for me, despite not having a Lexus with the Mark Levinson treatment.

used to driver better autos than now, but saving on gas is big deal for me due to the substantially larger driving distances.
before that stock volvo system inside XC70 is fantastic. can't say anything wrong about benz E300 driven prior with harman kardon. I also liked system in 1983 Fleetwood Brougham used to have prior. In Cadillac after auto CD-players came in I didn't want to replace the stock one at all and rather recorded CDs or LPs onto tape and listened there. I have a secondary weekend-driven '94 XJR convertible in collectible condition and admire that original sound system lots.
nowdays i drive '14 subaru XV Crosstrek and would probably think replacing just speakers that don't seem to handle enough bass. the rest of electronics seem to be fine.