Pros
Quality of co-workers is good. So you are not stuck due to incompetence of someone else (atleast not for long) as often happens in service industry. If you have the right level of assertion and execution capabilities, you can get good visibility which you can utilize to get faster promotions.
Cons
If you are at non-management level, Increments will be getting tinier year after year; and if you have entered on lower level of salary band you will take years to reach a decent level. Strongly advice to enter only at higher levels to enjoy better raises and faster promotions. Else be prepared for a stagnated career. Going towards the service industry way. Employees were once considered asset (maybe they are still considered so in few geographies). Now its a body shop. No career path. People are stuck doing same stuff with no visible career path. No onsite opportunities. Compared to service industry, the salary will only be 20% higher in most cases or atleast that will become the case in 2 years time once you join. In my opinion, service industry provides better career path, opportunities; though the base salary may be a tab lower than JPMC