Vantaggi
Personal development opportunities, especially for training, are good. Training is available through onsite courses, the web, and other avenues. Travel is often (not always) available for courses that are not taught at your location. If enough people at your location want a particular course, it is usually worked out that a class can be scheduled at a regional office. The company makes a big deal out of keeping current and mapping out and following a training path sutiable to each person's level and required skills. Compensation is fair for the industry, at least in the regional offices - I don't know anything about the DC area - and the benefits package is equal to or better than most companies I know of.
Svantaggi
As with any company supporting the government, there are times when the government puts out an unreasonable deadline, either for a report or for a proposal, and you have to do whatever it takes. This can involve long hours and unusual time away from home, sometimes including travel. In my experience, the company is good about providing food, etc., to make late-night or weekend efforts a little easier and allowing for compensatory time off. The career path for those not working toward senior management was, and remains, a little fuzzy. The Associate level is where most people spend a long time, and splitting it in two would be a good idea.