Pros
Constant growth creates great opportunities for people. Lots of knowledge sharing and support for innovation. Great people & collegial culture where everyone helps each other. There really are no politics Travel model makes work-life balance possible. It's generally not a 4 days on the road/1 day at home job. Clients are located near the offices, so travel is typically quite limited, so you can have a life at home. Work actually gets implemented, so you feel like your work matters People are humble. No big egos like you often see in the big strategy firms.
Cons
Standard downsides of consulting: unpredictable hours, some clients quite demanding, experience probably varies considerably depending upon the teams/people you work with. People development / coaching could be better