Mr Glass
751
The 5990 is one of the most versatile watches out there, especially for travel fans.
One of my candidates for "only one watch" collection. That and the new Casio BX5600
Since I love travel watches, this one is close to a perfect watch for me (and nothing will ever be perfect).
I know some prefer the thinness of a 5711, but I don't mind at all the extra thickness, for so much extra functionality.