Vantaggi
Flexible scheduling, retirement account matching is very good. Student loan repayment, and tuition reimbursement generous. Noble mission, like minded technical co-workers. Often less constrained on execution than working in government directly.
Svantaggi
Projects vary widely. Some are good, others ... not good. If you're a hands-on technical person you may be the only such individual on a project. There isn't a "bench" between assignments. You will be pressured to bill "directly funded" projects, take vacation time, or leave the company. For the Data Scientists out there, not many opportunities for *real* "Data Science." You'll see. Too much time in meetings talking about work instead of doing work. Hard to find good assignments. You're constantly hustling to drum up work instead of doing work. Projects constantly under resourced. Constant struggle to get the job done when you've got senior executives billing your projects behind your back. Pay isn't competitive with the private sector, other benefits losing value against competition. Recent exodus of experienced, top talent to better opportunities. Current employees, don't get left behind with those who can't leave. New hires are inexperienced recent grads. If you're experienced you'll spend a lot of unbillable time getting them up to speed. No real opportunities for training. The quality of courses in the MITRE Institute is a joke, and you're often on your own to cover your time taking those courses.