Pros
RAND is full of brilliant minds. Folks of all disciplinary backgrounds come together to work on really interesting projects that matter to policy realms, not just in the US but globally. There's never a lack of interesting projects--it's a candy store, nay, a candy factory for nerds who want to apply their minds to some high profile challenges we face today. Amazing location (SM), by the Santa Monica beach/3rd street Promenade, great weather, flexible work schedule... I can go on and on.
Cons
You make your own salary--if you have projects to bill, then work on as many projects as you need. If you don't, then you gotta scramble. It keeps everyone on their toes and is an interesting incentive mechanism, but it could be stressful if you're in a field where money is tight (i.e. non-defense or non-health research areas).