First of all, I would like to apologize for not attacking anyone. Personal attacks seem de rigueur around here these days. Maybe the days of cordial conversation are gone?
5% of your CDs sound harsh? That percentage sounds about the right. I suggest you do some research into the titles in question to find the best sounding versions of the offenders (if they exist). Would be a lot cheaper than replacing components.
Even after doing this I have a few titles that are near unlistenable.