As others have said, it really depends on the size of your wrist and your overall style. I just picked up the new Seamaster 300 as my daily wearer so my opinion is just a little biased. 😀
With that said, here are a few things to consider.
1. Unless you like heavy watches and have a large wrist, you probably would not like it for a daily wearer. Only way it would work for me is in titanium.
2. I had the older version of the Seamaster Pro diver, and found it a little blingy (lots of reflective surfaces) and the bracelet is a little too dressy for a sports watch IMO. But, if your office environment is on the dressier side and you want a little flash, it's a great option.
3. The Globemaster is the dressiest of the bunch, so I'd really only recommend it if you wear a suit at work.
4. The Seamaster 300 is the most casual of all three with minimal bling, which is why I picked it. It does not have a date, so if that is something you really look at on a regular basis, you might miss it. It does have a quick-set hour hand, though (jumps in 1 hour increments), which is useful for traveling between time zones.
Movements in all are comparable (although I don't think the PO is Master chronometer certified, but that isn't really a big deal). Whatever you decide, let us know!