Pros
BambooHR is one of the few places that actually practices what they preach--a company whose emphasis in the market is "setting people free to do great work" is doing just that internally. The company values like Be Open, Assume the Best, Enjoy Quality of Life, Lead from Where You Are, Do the Right Thing, and Grow from Good to Great are actually practiced every single day--albeit imperfectly. These values are exemplified by leadership, and they are super careful to preserve that culture as they grow. BambooHR also really seems to have work/life balance worked out really well--it's intense, focused work while you're at work, so you can feel good about going home at 5 and focusing on developing on a personal level.
Cons
As Bamboo grows, it can begin to lose the "family" feel, so a lot of individual effort has to be made to stay connected to people across departments.