Pros
Above average salary for some positions. Great contacts, experience, exposure to Gov and DoD contractors. Depending on what you do, you may have to travel a lot and do some interesting jobs and places.
Very patriotic and pro-veteran work environment. Great holiday parties, bonuses sometimes, fun employee activities on occasion.
Cons
If management decides that they do not like you, for real or perceived reasons, you are gone. Management style is like being in a dysfunctional family - certain people are golden, while others are cursed no matter what they do. If you are a golden employee, and you get to non-golden status, you might as well quit. Travel can become tedious for some positions. Management is "penny-wise" but "pound-foolish" - For example, they will go nuts over the smallest unapproved expense, walk around and turn off monitors at night, ban at-desk coffee makers, yet continue to pour tens of thousands of dollars (or more) into inefficient or wasteful processes, at times not provide engineers adequate tools/equipment, keep people in the field for weeks that aren't needed, and fixing products for customers at their own expense rather than making sure things are done right in the first place. Questionable HR practices (firing, etc.). Assistants, accountants, and those with daily direct contact with upper management probably take the brunt of abuse.