I agree with all you say .... it really is a beautifully constructed engine that runs as good as it looks!
My one minor disappointment with it is that it only seems to pump water very weakly, more of a dribble than a stream. But then considering the size, it is somewhat amazing that it pumps water at all!!!
Perhaps the pump could be checked to see if maybe better seals or piston rings might make a difference? I haven't done that yet, but it is on my list, at about #1,097,342