I have a much better car stereo than you, I guess. I most certainly am noticing, and have been using it for the last five years in my car.
Mate - people can't tell the difference between lossy and lossless on £30,000 speakers in a world class acoustically treated studio. With the best "car stereo" in the entire world, even sat stationary with no road or engine noise you wouldn't be able to hear the difference. So no, you're not - just enjoy ACC via bluetooth its more than enough for your needs (that you've been enjoying for the last 5 years anyway).