Pros
The firm has many name-brand clients and lots of opportunity. I was in the Federal Tax group. The firm is trying to act, look, and operate like a Big 4 "with a heart". The staff are in general treated fairly well, especially when they are new. The firm is trying to attract high-quality candidates and make a lot of positive promises, some of which hold true. I think their heart is in the right place. Salaries appear to be at or slightly above market at most levels.
Cons
Depending on the office and your immediate superiors, this could be a good or very bad place to work. Management goals are inconsistent and managers and partners fight for resources. The management infrastructure is there, but execution is only mediocre. The firm is always trying new management methods, styles, etc., but with only so-so results.