Pros
From what I've gathered in my 6 years at BRG is that they hire the best people from some of the largest organizations around the world. I'm always impressed to hear that many others in the industry know my colleagues and recommend them highly from the past. Working with this caliber of people makes my job much more challenging and rewarding. They are also constantly hiring and expanding. The culture is what makes this company fun and casual to work for. The work/life balance is great and you manage to make long-time friends in your colleagues.
Cons
I don't think BRG can compete with some of the benefits from the Fortune 100 orgs out there, but what it lacks in benefits, it makes up for in the following: Alternative Work Schedules; Alternative Work Locations; Varying Client Involvement; Executive, Director, Manager, and Direct Report Collaboration (the hierarchical concept doesn't play a large role here - everyone collaborates together); Amazing Technology and Tools