Pros
There a lot of great, talented people to work with and learn from - but, this is almost always the case at ad agencies. Monthly financial meetings were refreshingly transparent. Made an effort to create a culture. Though money-hungry, I don't think many of the owners/management are truly evil (definite exceptions)
Cons
None of those great, talented people you'll work with or learn from are in management positions (definite exceptions). There is a clear divide between managers and their slaves. They are feared instead of being viewed as mentors, and some are just downright awful and mean. The agency is literally segregated in half: one side traditional and one side interactive. This approach is completely dated and is a disservice to clients who should expect efficiencies from going with one agency for both sides of marketing- instead, they get two account teams that never interact and lack a full perspective of the business. Interactive side is volatile- high turnover, mean/incompetent/unavailable managers. It is common for the agency to lay off en masse when financials dip and managers do little to help employees feel less anxious about being just a number. No training whatsoever. No forum for ideas. Avoid if looking for entry level positions - expect a low salary, no potential for growth, no training, extreme pressure, little appreciation or acknowledgment.