OK -- let me start to work on an answer, expecting that I may not get there in this message, but will at least have eleiminated a few that are / were on the "short list". I will likely continue this message, as time permits.

Last week, I put these two on the short list. I love the GMTs, and these two are the favorites in that category.

. . . and like anyone considering this question, there are the "classics" -- Carrera and Monaco, so let's get those two out of the way.

But, if I could only own watch, it probably wouldn't be either of these -- the Carrera would get a bit boring as a daily wearer; the Monaco is just the opposite, too loud for some situations (say, with a tuxedo).

If I had to wear one every day, 365 days for the year, it might be this one, which does get lots of wrist-time of late.

but, again, there might be situations where this clunker, in its military olive drab, would just be too much . . . and for this reason, I won't even put a Silverstone on the list . . . just seems like to much to wear 24x7x365.

which takes me back to this old favorite . . .

yes, it's a "tool" watch, but it's not so big that it screams out at people across the room; it can be hidden under almost any sleeve . . . and it's very rare, so if I could only keep one, this one might just be the most difficult to replace.

. . . and speaking of scarcity, how about this Carrera 12 Dato? It would take a while to find another one of these, and I really do enjoy wearing it.

TO BE CONTINUED . . . at least I have taken a few off the list [Carrera, Monaco, Silverstone and the Green Guy (and I suppose the Pewter Guy, as well)] . . . for the moment, the "short list" will consist of an Autavia GMT, the first execution Autavia and the Carrera 12 Dato.