Hi Old Groucho, from your handle we may have a couple of things in common!
FWIW I heard The Orpheus at a meet. I was able to have a few listens during the day and the rest of the Sennheiser lineup.
If I could have taken a rig home with me it would have been the HD 800 with the 800HDVA amp DAC.
I expected The Orpheus to sound like angels farting into my ears but I guess technology has moved on.
The 600's came close to the 800's IMO and at the price are an absolute bargain.
I feel fortunate that such quality is available at a price that would not even get a sharp word from my wife!