Red sold one a few years ago and it went for quite a tidy sum. I read some time after that one of the companies that formed Acube (maybe soft3) were selling them off relatively cheaply either towards the end of the 90's or early 2000's. Wish I 'd known about it as I'd have snapped one up for myself.
I was tracking these things way back when they were in development, but I had no idea they ever made it to market until Red's sale a while back. I think they could have sold a ton of these if people actually knew they were available. So unfortunate...