I picked up this used binoviewer (with Baader prism diagonal and glaspath compensator) a while ago and haven't used it more than a couple times (been imaging).
The prism is definitely dusty and could use some TLC (lower-right picture, though no scratches I can see, just the normal crud that accumulates on optical surfaces). The glaspath compensator looks fine though there's a small smudge on it (lower-left picture, smudge just above the two circular reflections). The eyepiece outlets are sunk into the binoviewer a bit more and appear to have proportionally less crud on them.
Planets look great and snappy through the setup, feel free to swing by if you're local and want to check it out before you buy (Bay Area, California).
I'm asking $850 shipped.