Pros
I was in a smaller team, so it was excellent collaboration environment. There are ALOT of opportunities, as long you go looking for it. I got to interact directly with the director for the team, and had the chance of doing presentations to one of the SVP. The office was casual and people was friendly. There were casual Mondays and Fridays, and I could approach anyone in the office for questions. I was in the Data Center though, so it was more casual than normal banking institutions.
Cons
One of the downside would be the number of levels and bureaucracy, it is hard to avoid with any financial institutions. Any major decisions needs to move up the ladder, then come back down. It gets tedious and takes much longer, but it comes with any large institutions