Pros
1) The payments business is fine people. The core business will continue to make a lot of money - for now. You'll be working for a stable business that is doing quite well. 2) Good work life balance in a more relaxed bank type atmosphere (still a bank though as you'll see below) means you'll see your spouse and kids and never get super stressed. 3) If you play the game and are a good worker - your loyalty is usually rewarded. You'll move up and while compensation is not stellar - a top performer will not have too much to complain about on the comp side.
Cons
Here's the thing. If you're interested in working at AMEX because of what you read or see in the press - take a closer look. This is a bank first and foremost. The cool stuff you see and hear about is about 1/1000000th of what really goes on and a cloud of PR fluff. If you accept that and are still interested that's fine and to be fair, the cons of what you'll find here are probably no different than any Bank job you'll see on Glassdoor: 1) Lack of risk taking. Senior management will always take the safer route or one backed up by overwhelming evidence. We're a BANK. With a lot of regulation and oversight. This usually means following the middle ground or being late entrants. You'll have good ideas. Your co-workers will have good ideas. If it's risky though and unless it comes straight from the top down - your idea is guaranteed to go no where beyond a deck. You could spend a whole 12 months writing a deck about stuff you'll never get out the door. It's amazing how the year-end cycle comes and goes and the only tangible output people have is a whole lot of documentation about what we would "like" to do. Crazy! 2) Overuse of the word Innovation. People love to throw around the word innovation. It's like people using the word API in their pitches but can't even explain what REST is. Innovation to your managers is different from what you think (or would like) innovation to be. Innovation is cost-efficiency, it's taking an existing process and fine-tuning it or a big biz dev partnership. It's not hacking away like a startup or being agile (don't get me started on agile). 3) CYA, CYA, CYA. There is a lot of covering going on. Due to the hypersensitive combination of bank, lack of risk taking and personal ambition - you get a lot of meetings and calls which really are for the purpose of individuals to cover their rear in case things go wrong down the line. This creates abysmal layers of bureaucracy. Next result: slow like molasses to get decisions and things done plus watered down outputs due to design by committee.