Pros
As in any office environment you will meet great people. If your objective is to learn, you will find how/what and people who can help to develop/advance your skills. With a bit of effort of finding good reasons and mentors you can learn a great deal and get exposed to multitude of practices/industries. Variety is truly abundant, but you have to hunt for it despite every team being understaffed - nothing will be presented on s silver platter.
Cons
Leadership is nonexistent. PPD are rarely present and have little interest in their people. High turnover for managers and seniors. No staff. Little to none outsourcing support. If you are a manager/senior you will do jobs of at least 4 people in addition to training armies of interns. You will hear "open door" policy a lot, but God forbid you will mention anything negative. No one wants to hear the truth. Promotions are based solely on personal friendships. Thus, top heavy firm with no recognition for lower ranks. Bonuses are a joke.