Pros
The money is decent, depending on the Captain that you find yourself working with. Some Captains seem dead set on just saying no to everything. These tend to be very unhappy people. In which case it reflects back on the office for hiring people into a position of authority that they should not be. I had not meant to turn a positive into a negative, there.
Cons
Spending a lot of time away from home, it is sometimes easy to begin to feel that the office and the ship personnel are two separate entities, that we are not working with anyone from the office. For instance, when trying to access the internet ( a thing the ship's do not have, enough though it is 2013 - in Japan, outside an APL office with open internet connections, we were told by another APL employee that we were not allowed to use this open broadband connection. This is not cool.