Pros
The best reasons to work at Kaiser are the pay being fairly high compared to other hospitals and your retirement benefits. Unlike many companies Kaiser still offers a 401k match and a pension for retirement.
Cons
some of the cons of working at Kaiser are the demanding hours and tasks due to constantly being understaffed with physicians. You will most likely be staying past your clock out time on a daily basis. Another big downside is the seniority priority rules when applying for other positions (which also makes it hard for new employees to get in with out a referral). Some of the positions I applied for to move up had many other employees (some not even from the same department or with out any experience doing the work the position was offering) but they had been with the company for 30 years or so (longer then I was alive at that time) so there was no way I was going to get that position over them. You will need to work for a loooooong time at the company before you start moving positions.