I'm not sure if you are set on a Pam or not, but I would browse the forums a bit more before you go with a Pam as a first rep. I've been a member for 7 months or so and now have 10 reps and I love all of them.
If I were you I would go with a nice Breitling Skyland Avenger V3 or Swiss SFSO. These two watches are perfect IMO. The can be matched up with a SS bracelet for all occasions, a rubber strap for the summer look, or a nice custom leather strap for a more dressy look. Your common civilian will not know a Breitling and will think it's the most kick a$$ watch they ever seen, it will take either a fellow rep aficionado or an AD to spot the "tells", and you yourself will sometimes forget it's a rep. There not cheap, but you can also find them for very reasonable prices if you hunt around.
The Omega UPO is a nice watch, but Omega is more well known and the crystal will need chief's AR treatment for the crystal or it's a major tell IMO.
Only reason I try to steer new members away from Pams right off the bat is because once you buy one, next thing you know you have 4 Pams, 9 straps, and no money:)
You can't go wrong with a Breitling. I love em.