Pros
Co-workers are very professional as there is zero tolerance for anything less. This is great place to learn how to do your job well as the pace of work is slow compared to corporate america. I learned more from my coworkers in one year than in 5 years at other companies. Anyone average or slightly below exits the company in less than a year due to management's creative ways to ensure a certain level of performance. This means you almost NEVER have to worry about incompetence. Its truly a unique work environment.
Cons
There is almost no upward mobility and a lack of recognition for individual performance other than you get to continue working there. Managers are working managers with minimal time to do anything other than their own job. There is no career development. Goal setting is 'go-through-the-motions'. Groups operate in information silos with little incentive to integrate such that there is a lot of redundancy. Management's take on turn-over is people come and go. Even if you are the best ever, don't expect anyone to care when you leave.