There are a lot of interesting thoghts coming out in these messages, and I must admit the poll results themselves are a bit more pro-ebay than I expected. I started this poll yesterday after winning an ebay auction for what appears to be a very good condition Scubapro Mk 10/ D-300, I am guessing vintage about 1988, but last serviced sometime in the last 10 years or so. The seller knows nothing about the history, claims it was from a shed being cleaned out. It is a real mix and match though, early '80s vintage scubapro console (blue/white), Mk 10 with flat screw, but big drain holes (therefore the 1988 guess, I have a Mk 10 bought new in 1987 that is flat screw, small hole, and know they went to round plastic head screw around 1989), the more recent service guess is based on the the Air II hose, it has the newer smoother styled knurling on the disconnect that came out in the late 90's. Who knows it may turn out to be a paperweight, I will not know until it gets here and I take it apart, but for $58 it was worth the risk.
Ike