Pros
Overall, I would work at American Express again. Good culture, but that can depend on which organization you work in. Certain organizations do not espouse the Blue Box values. Good work/life balance. Same caveat. Good vacation allowance. Great direct management and good management one to two levels up.
Cons
Salaries near the bottom of the industry and comparatively poor against other companies in like for like roles. US citizens have poor job security. Watched many talented individuals lose their jobs so that the company could hire replacements in India. Not because those individuals did not perform well, but only because they were tenured and at the top of their pay ranges. Three levels up and further, they're typical executives that see you as a cog and not a person. They see your work as dollars that make up their bonus. They make changes, not because they're beneficial, but because they need to put their stamp on things.