Pros
If you can land the right assignment, it is a good place to start. Make sure that you work closely with your resource manager to get great assignments that will advance your career.
Cons
Poor senior leadership. Most know the consulting business, but have no clue as to how to manage an organization. For a company that its major asset is human capital, they have no understanding of basic human resource management. Make sure that you work closely with your resource manager to get the right assignments to advance your career. You will really have to apply yourself to make this happen. Leadership is not likely to move you to an assignment that will advance your career if you are working at another client. Try to avoid being bounced around from PM's or MD's as much as possible. You can very easily fall through the cracks and not get noticed for salary reviews and promotions.