Pros
While working at the agency, you meet a lot of others in the entertainment field and many move up in the field after working there. APA also promotes from within, so it's a good place to start if you want to be an agent. Compared to other agencies, APA is extremely laid back and employees are generally treated with respect. Agents' doors are always open.
Cons
As at any agency, the pay is very low and hours can be very long. I regularly worked 10-11 hour days. The agents are working in a competitive industry and are always trying to get ahead. Their stress gets passed on to their assistants, so the job is nerve-wracking and agents sometimes yell. Since APA is not as well-respected as other agencies, it might be harder to get a higher paying job after working there. I changed industries after working there, so I don't know.