Pros
Great vacation policy (160 hours/year, but more is allowed as long as it gets approved). 9/80 schedule so every other Friday you get off. Not cutthroat, just do your job well and in a reasonable amount of time, and you’ll do fine. Putting in overtime is not forced nor necessary to do well as long as you get your work done.
Cons
Chances of getting a raise/promotion really depends on how much your manager cares/likes you and not necessarily based on your skill and contribution to the company. It varies. Best way to get a raise is to get an offer somewhere else and have them counter. Sometimes you may go above and beyond the call of duty for months, and all you’ll get is a gift card. I believe that having a clearance will afford you some extra favorability—they usually approve more vacation hours (200 hours easily, and more if it gets approved), and promotions seem easier to attain because they want to keep you after spending so much money on security clearances.