Pros
9/80 schedule and you don’t have to do much. Interview is easy due to lack of talent inside of the company. If you have a clearance you can pretty much vacation and do nothing with your day. Not much is expected of employees. You get to work on obsolete stuff which can easily be looked up on the internet, if you choose to take that initiative. Hires and promotes based on affirmative action tax incentives (this can be good or bad depending on your situation).
Cons
Benefits are pretty stripped in the details and erode over time, low pay, and promotion granted on time with company (as opposed to results). Hire and fire defense contractor. What is most profitable for the company is contract extension, not a successful result/product/etc., meaning failure is more profitable than success. There is a real stigma in the commercial space against former employees from this industry due to their lack of ability to deliver and title inflation, which restricts opportunity down the road. Summary layoffs are often defense industry wide due to acts of congress, so be prepared to be unemployed for quite some time. Be aware of heavy nepotism and other favoritism as management often knows the government budget years in advance and will earmark positions for relatives and friends.