Pros
If your are and MFTI, this is the best place to get your hours. Lots of client contact and you can earn 8 hours a day. A great place to discover the mental health industry and can lead to a career as a therapist. Occasionally it's very rewarding on a personal level.
Cons
If you don't have a real strong purpose for working with the mentally ill, this job can eat you up. You have a lot of autonomy (little supervision) in dealing with some of the more acute mental health clients available. You will be in close quarters with all manner of mental illness for hours at a time. It didn't help the counselors that for years, Kaiser was pinching their budget for mental health services (and got sued for it). The generous time off package is the most reliable support you will get.