Pros
The company provides great opportunities to those who are capable of creating relationships with the small community of people who do the work. There is no shortage of challenging, rewarding work to do and the people (who do the work) you get to work with are top notch. Transfers between groups are easy but if you want to "climb the ladder" look elsewhere. The senior management positions are for life and to get promoted someone has to retire or pass away. On the upside you can be rewarded for your hard work with out of cycle pay raises and a nice bonus around Christmas time. The 9-80 work schedule is really nice too. The culture in my group encourages a strong work life balance and you are not disturbed on your time off.
Cons
There is a lack of accountability at all levels of the organization which make it very difficult to maintain a schedule or adhere to a budget. This, in turn, creates a culture in which to slide is normal and there is no sense of urgency to any program or project.