Pros
Kaiser employees are super mission-driven and focused on doing the right things for members and the communities the organization serves. The IT organization, where I worked, has a really tough job trying to drive innovation through a change resistant culture; they hire top notch talent who are rock stars in their prior industries. Compensation and retirement packages won't make you rich, but they are fair and will provide some security. Health care benefits are awesome.
Cons
Driving change at KP is like trying to ride a bike through molasses. It takes an extraordinary amount of effort to change the way things are done and adopt modern innovations, partly because within health care, half baked processes can cause people great harm. However, KP's culture extends this conservatism and "analysis paralysis" into all of its business practices, not just clinical ones. To work here and make a difference, you have to be very patient, and figure out which execs have the organizational power to move your ideas forward, and then work through them. Some employees have been defeated by the inability to make progress, and there is somewhat of a free-rider problem in which a few employees take on most of the work while others do the minimum.