Pros
Career opportunities and professional development are stressed at Booz Allen and if you are driven individual you can achieve very satisfying growth with this firm. On the other hand you can also settle into a slow steady growth if you are happy to just do your work and go home. These options will allow anyone to be satisfied with Booz Allen as an employer. Above personal growth the people that work for Booz Allen are of the highest caliber and create a work environment where your greatest resource are your peers. The wealth of knowledge and experience is a great place to work and learn how to excel as a government consultant.
Cons
The bottom line is that Booz Allen is a very large firm, as a result there are certain aspects of the organization structure where you really feel like a small fish in a big pond. The assessment process is annual and a pain and most likely isn't structured as effectively as it could be. Also your experience is contingent on the contract you work on and your senior management. I know of people who had pretty bad experiences getting stuck on a team with a boss that didn't care about their growth and work that was boring. It can be hard when you find yourself in that position but then one of the benefits of a large firm can shine through when you transfer internally to a better position.