Pros
Challenging work is generously rewarded. There are many opportunities for learning, education, training and advancement, more so for younger workers when the coming wave of baby boomers retires in the next 10 years. Under the National Security Personnel System (NSPS), a 'pay-for-performance' system, extremely high performance is generally rewarded very well; young performers can advance quickly up the pay scale. I consider myself to be extremely fortunate to have worked my entire career as a US Navy civilian, beginning as a GS-2 and working up to GS-15.
Cons
NSPS is viewed by many as lacking in fairness and objectivity. While the US Navy is a 'high-performing' organization, some organizations are poorly managed and some areas are somewhat chaotic.