Yes, agree. CBS FM sounds horrible. It's a sort of 'mono/AM-ish' sound, less stereo separation and very dry and flat. Not that typical 80's-like processing, what suits the format of the station.
When you first tune in to CBS FM and than Radio 103.9 it's really, really different, open, wide and fat. I think when CBS sounding like Radio 103.9 at the moment, it makes a big difference.