Pros
This is a top rated Company.
Competitive pay and benefits.
On the job training.
Work with highly educated, skilled employees and management.
Open door policy.
Stability and flexibility with schedules.
Clean, safe quiet work environment.
Ability to go from mail room, to head of department very possible.
Constant contact with highly educated and connected clients.
Senior Management is very capable.
Company holiday parties, bonuses and equal treatment for everyone right down to interns.
Job security. Pay raises regularly.
Cons
Small company and building means cabin fever kicks in fast.
Busy work during slow business waves, means doing something outside of your job scope, often. But this can be an advantage, because they recognize it. Senior management is highly qualified to be there.
Small company means you aren't getting experience in a large business environment, and that shows at interviews. Also, pay is great, but not fortune 500 pay. And you may get very far, but you aren't doing it at a large corporate office, so again, you might being comparing apples to oranges at a fortune 500 interview. But with skill in interviews, this wont matter.