As far as Maxell UR cassettes, I found a few of these in sealed condition, and recorded a jazz mix tape for TH member, ianC90. I haven't tried recording on the current Maxell UR tape, but I did receive a current-release Maxell UR 90, with progressive rock titles, recorded by TH member, Arnold Layne. And I was duly impressed. He recorded with his Nakamichi Dragon.
Nando.