I jammed with a guy that had one in his jamroom that needed some work. I tried to buy it off him but he would not give up the amp. Adding insult to injury he was a bass player not a guitarist so he had even less use for the amp.
Back in the '80s I played one for an audition, it came as part of the rented rehearsal space. I didn't really use its features, though, just dialed in the dirtier of its two channels to sound like my single-channel JCM800 combo.