Well, the auction ended a few hours ago, and the 4344MkII was sold with a winning bid of about $4K. Less than what I paid for at a local audio store, but much more than what I'd get by selling to a business, so I'm happy.
Also, I came across a Pass X150 which was being offered at very appealing clearance price which I just couldn't pass (excuse the pun) up. I decided to sell my present Mac MC300 amp, which has a 'sell' value that is much more than the price of this X150.
Ian, although it's not a X150.5, the newer model, the X150 sounds wonderful! The overall tranparency of the sound improved, as did the sound stage imagery. I also don't notice any reduction in power. Best of all, the bass is more tighter, less boomy, more controlled. I believe the Pass is a better match, for me, with the 250Tis. So, thanks for your recommendation.