Quote:
With commercial CDs, however, many have a harsh zingy quality which is very obvious in the car and makes me want to switch off after a few minutes. Home burned CDs from either vinyl transfers or downloaded MP3s don't seem to have this problem.

That sounds like something that could easily be solved with a little EQ. Painstakingly re-ripping a bunch of vinyl records sounds like going the long way around to me. But suit yourself. If you've already found some vinyl rips and you like their sound, then by all means carry on!