Pros
The mission of working for an organization whose purpose is to care for sick children (esp. those who cannot pay) and find cures for disease and illness is hard to beat. Overall the organization values work life balance. For a non profit, pediatric organization, it's compensation is ok, benefits are great.
Cons
It can be surprisingly bureaucratic as it is a very consensus driven culture. That can be a con and can really slow down the pace of innovation in some areas. If you are in a non direct patient care related role (like marketing/IT, etc.) don't expect to find an organization where you will be able to truly innovate. If you con't care so much about that, it can be a very solid place to work. If you are in tech/IT our salary here will be under Seattle market value by a good 20% at least. But it's stability and mission can offset that.