Pros
JPMC is a huge company so there are a tremendous number of opportunities in the organization. You can find roles in any sector of financial services within the company. The stock price as gone up 250% in the last five years so if you take part in the purchase program you should benefit.
Cons
The firm is more generous to outside candidates for open roles than to internal candidates. Your salary in a new role is not based on the role but it is based on what your salary was in your last position. As a hiring manager, I could bring someone from the outside in at a specific salary, but even if my internal candidate had superior skills and was a better fit for the role, I was capped as to what I could offer based on the internal candidate's current salary. As a manager it was incredibly frustrating. If you are on the Operations teams there is very little opportunity for significant increases to your compensation. Even if you are promoted, there is a cap on what is offered, even if your comp is below market. The only way to get a respectable increase is to leave and come back to the company after a time away. The Operations teams are treated like 2nd class citizens. The business will report record earnings but the bonus pools for the Ops teams will be flat year over year.