May I suggest a new contender: the Blancpain Aqualung. It looks very similar to the Explorer, with the added benefits of a larger case size and date window. The older version that I own is 38 mm with a small date window. The newer version is 40 mm with a big date window.
Appreciate the suggestion- the small date window version is nice, but not quite what I want.
Unless something comes out of the blue, I am down to the IWC Mark XVI (black face now, finally saw one in person), IWC Portugese Chrono, and Omega SeaMaster Aqua Terra Auto.