Pros
Perkins Eastman does have a good management staff who seem to genuinely care about their employees (even if they don't always understand what our needs/concerns are). There seems to be a good base of knowledge and there are forums available for sharing that knowledge across various offices - it's up to employees to overcome the distances and communicate with each other.
Cons
It's a huge company, so there's virtually no opportunity to identify a problem (in terms of operations, etc.) and actually get it fixed -- everything has to be vetted and approved by dozens of people, and even if that happens (which is rare) there is still no change because you have to overcome the culture or habit of nearly 1000 employees. The biggest con in my view is the seeming lack of design integrity. There are some good projects, but the overall portfolio shows a lot of mediocre work. Rather than trying to improve their existing staff or project base, the strategy seems to be to buy up other companies who are good at something. These guys are expert "mergers". The ability to compete in many market sectors is good, especially in a tough economy; but they aren't the best at anything.