Pros
Plenty of opportunity to work long hours which, in theory, will advance your career. Exposure to multiple clients in various industries provides for great learning experience. Work arrangement can be flexible, some opportunity to work from home depending on which group you are in and the time of year. People are great but most are exhausted so they eventually leave. There's always someone to help if you have questions. Some partners better than others in terms of how they treat their staff.
Cons
Depends on which partners you work for and which group you are in. Overall, long hours including long weekdays and work on weekends. Hard to balance work life especially if you are in a role that requires travel. Internal competition between partners can create difficult work environment due to politics and who can claim fee revenue.