Pros
You learn a lot and it changes you as a person but it comes at a big expense of personal life. Lot of people say that ATK dose too much of procurement but still you will learn a lot about the category that you are sourcing so you will always be learning. Also if you are aligned to an account, you will likely progress very fast as you will have good utilization and a network of Partners
Cons
It is a show off culture where working until 2am is expected and appreciated. Consultants will hold on to sending emails after midnight to show their Partners that they were working late even though deliverables may have been ready earlier in the day. I understand that there will be projects that will be high burn but you just do not have to make every project very stressful - particularly by having endless reviews of the decks. Most of the Partners and Principals are always frustrated and will take it out on you. Worst is taking out on your right after a workshop when you were working 20 hours a day to prepare. There is absolutely no concept of work life balance. So if you are young, join the firm otherwise don't even think about it. On top of all this firm messed up their bonus structure in 2014 leading to loosing its best consultants to McK, BCG, Accenture and EY.