Pros
It's easy work, and it's very predictable. Once you pass probation, it is difficult to get fired. The people are generally nice, the work is easy, and the benefits are great. It also looks really good on a resume. It's been said that people either work here briefly when they're young for the experience and resume padding, or they come when they're old for the retirement benefits and low-pressure work environment.
Cons
None of the women that I know in technical roles at the lab are having a good time--including me. Most of them have faced harassment or discrimination, and management has largely turned a blind eye or has even been the source of the issues. It does seem to be better if you are an engineer, for what it's worth. It's also nearly impossible to get promotions or raises that even match inflation--for everyone, not just women. Several of the people I work with have been here 5 to 10 years, and they are making less than me; I just started a few months ago and didn't even negotiate my salary.