Pros
For all US federal agencies, the work you do is important and contributes to the bottom line for the taxpayers. It's challenging and has great benefits. Depending on a person's skillset and qualifications, the pay is generally pretty good. Being part of a mission-focused organization is very personally rewarding.
Cons
Working for government is very challenging in that politics rule the day. Unlike the private sector where a company might invest more funding into a well performing program. Program performance is rarely the metric that determines investment levels and this presents an infinitely uphill climb to make any progress. While pay was also listed as a positive, if you are an extremely well qualified and high performing individual, your pay likely doesn't reflect your value and there's no way around that because the pay structure is antiquated. This has a negative impact on recruiting, as well.