Pros
Working with some really great people and really great clients. I derive a lot of job satisfaction doing everything I can for our best clients, some of whom are just a pleasure to work with. Aon has some seriously talented insurance specialists in their respective fields (environmental, management liabilities, claims, etc.) My work is also mostly challenging, varied, and interesting. Decent work life balance, too. Compensation is also decent and not terribly out of line with the other big brokers. My immediate boss is also outstanding and I've learned much from him over the years. I'm lucky in that I have a very short commute.
Cons
As one client said, "Aon can put together a $1 billion plus insurance program, but can't get an invoice out." Offshoring and outsourcing back office functions hurts the company in the long run. Absolutely horrible bureaucracy, especially with respect to IT. For example, I needed to update Java to access a prospects data room. At home, the process took less than 2 minutes. At work, after six weeks of trying, multiple layers of approvals and calls to India, I gave up. Contrary to "Client Promise", Aon will also sometimes put its internal bureaucracy ahead of a client's reasonable wishes. Too much "rah rah" buzzwords and silliness. No, your web survey isn't going to "revolutionize the insurance industry" no matter how many buzzwords you use to sugar coat things.