Pros
Super smart, caring, real people working on fun and challenging projects for world-class clients. As far as agency work and consulting goes, it doesn't get any better. Yes, it's important to have great ideas, work hard and make strong contributions at Quarry, but it's all within the context of a fabulous, caring and engaging culture. The management genuinely wants the best for everyone and strives to make that a reality. They listen.
Cons
As others mentioned, there is some turnover, but most people leave to get experience inside big companies or to follow an entrepreneurial passion, not to go to other agencies, which is an important distinction.