Vantaggi
I can only speak for the USA offices. There are some really great, talented people who work there who care about each other and the clients. There is an attempt at company culture, with a good amount of social opportunities available. Working with the people on my team was the best part of my experience there.
Svantaggi
Absolutely zero work life balance, with no overtime pay even for non-exempt employees. Upper management is very cliquey, and doesn't make smart executive decisions for their clients (or employees). Extremely disorganized managerially. They advertise themselves as a "growing" company because there are so many job openings, but in reality there is extremely high staff turnover because people are burnt out. Bullying from clients is normal.