I have two Citizen brand pilot watches.
I got one to commemorate passing my first checkride.
My wife gave me the second on our wedding day.
I sometimes wear one while flying, but they've never been useful. They both have an "E6B" dial, which is occasionally useful when flight planning (on the ground). They also do Timezones and ZULU time very well, which is nice when I arrive at a destination. But again, not much good in the air.
Honestly, the most useful watch for me in the air is a cheap sports watch with the ability to do multiple count-down timers. I set up the timers on the ground for each leg, then in the air, it can easily tell me how far ahead/behind my plan I am at each checkpoint.
There is a new generation of Flight Watches that is slowly becoming popular, topped by the Garmin D2 Titanium. These are more smart-watches than the traditional "swiss-style" watches. With a built in GPS, database of waypoints, moving map, and bluetooth that can sync with my iPad and on board systems, its basically a mini-glass display on your wrist. Variations run from about \$400 to \$900, so they aren't cheap (and I don't have one yet), but they are pretty incredible in their capabilities.