Pros
Relatively flexible on working from home or reduced hours arrangements. Standardised package of perks like insurance and pension - nothing not offered by the competition though. One of the big boys, so if you can survive in Jacobs, you can do well in any of the other competitors. Aggressive US leadership pushing for winning most of major UK projects, especially in London, so if in London you'd have relative job security.
Cons
Don't care what the end result looks like, as long as the anal QA checklist has been checked and the timesheets look good. Salary is sub-market average. Leadership is disconnected from local teams, poor leadership in crucial positions for various programmes. Horizontal mobility is limited managers prefer to waste talent in bench time than allow for easy movement across other functions. Then complain to talent for not having work to do and doing bench.