Pros
Amex really backs their employees - no one was laid off in 2020 despite the pandemic, and we were told that early on, which was amazing from a job security perspective. PTO policies are incredibly generous, and WFH flexibility was the norm long before COVID. There are great interest networks you can join to meet people outside your business unit, and on the whole, most people are intelligent, collaborative, and friendly. Steve (CEO) is likeable, honest, and his priorities seem to shift with that of his employee base (e.g. a strong emphasis on D&I in 2020 and beyond).
Cons
Amex pays about 30% below market value against other financial institutions. It is also incredibly challenging to get promoted at Amex, and you often get stuck in a role for much longer than you'd like. Even when you do get promoted, there are VERY stringent guidelines about compensation attached to promotions, so it's hard to secure a significant raise at any given time. The annual review process is also extremely over-complicated.