Pros
Very friendly work schedules. Easy to flex time for a doc appointment or family activities. 9/80 work schedule. Easy to move teams. You're treated as a contractor internally though you are salaried. If you don't like your job or team it's easy to move to a new project. Not a lot of pressure to work more than 40 hrs a week. Straight time overtime paid for hrs over 40.
Cons
They don't invest in the employees they have. They pay big sign on bonuses and enticing salaries to external hires and screw over the people who have been here for while. You will never get above a 2-4% raise no matter how hard you work. People who decide how much you get paid do not actually supervise your work. Promotions are a popularity contest and have no correlation to your actual work. If your section head doesn't know what your working on because it's classified you have no way to advocate for yourself. You have to beg for a raise here and even then they won't budge above 3%. They pay external hires more than internal employees. Work here for 2 years and then leave because over time they will just underpay you. Promotion only worth 3% salary bump is a joke. Should be more like 4-6%.