I have a Walkman WMD6, have had it for years, and really like it, but find that the bass recording, response, is very 'soft'; this is particularly evident when one A-B's it with a CD of the recording.
I was also startled by how Sony UXPro CrO2 (?) gave a much wider and more accurate stereo 'picture' with the WMD6 than the Maxell, Denon, and a couple of other tape brands that I tested at the same time. They sounded fine on their own, but in comparison to the Sony UXPro's really provided no broad spectrum; kind of 'crowded' everything in.
Most of the plastic and rubber (interior - capstan wheel etc.) components had to be replaced at one point, because of wear. You might want to bear in mind how easy/difficult it would be to replace these kinds of parts on whatever it is that you end up buying.
GVDV