Pros
Great pay for easy work, great benefits, almost no pressure. You will always feel confident that you are one of the best people in your field. Regular checks, standardized bonus systems make it easy to make a little bit more. If you have other interests on the side, it's easy to do, and you get to go to school for free.
Cons
There is no real focus on quality. The entirely political focus of defense products require projects to be subcontracted to shreds because they must cover as many political districts as possible, so maintaining quality is a nightmare, and creating a consistent product is also a nightmare. Management is incredibly understaffed and manage poorly. There is little emphasis on developing talent, so you basically sit at a cube working on your own. This is different from any team environment I've ever worked in because you really aren't working in a team. Everyone is spread out in so many different places that it's hard to keep a coherent understanding of what is being done. There are so many processes that you begin to believe that the company hired you, but they don't trust you at all to do the right thing. Why hire people if you already have an algorithm to do things?