"For random music, straight USB works fine, but I do listen to a lot of audiobooks, and unless you can correctly order the file names (which I do for this purpose) a playlist on an iPod works best through a car system."

I will definitely research your above statement. I will also research HD radio. Thanks!

It sounds like you are quite the car stereo tinkerer! Although I replaced my first car stereo back in '78, I have done very little modifications since then and have relied on the factory units.