Pros
The mission is totally terrific - we get to work on serious issues and events where what we find out often leads to real safety improvements, and the agency is well thought of externally. The staff is generally superb and highly motivated, and people like what they do. Not too many clockwatchers around - it's not that kind of job.
Cons
It's the government, so we're subject to all the current budgetary stupidity affecting everybody else, too. That isn't going to improve until Congress does, so don't hold your breath. Promotions aren't always based on managerial talent - laying low and keeping your nose clean works pretty well, as does avoiding making any controversial decisions. Because it is a small agency largely staffed by technical specialists, there isn't a lot of opportunity to move around.