Pros
Compensation - pegged at 75th percentile of market for average performance - in other words, you get paid as much or better than 3/4 of the similar positions out there. Benefits -- management fee rebates on Fidelity Funds make the funds extremely competative. There is a high value placed on integrity and doing what is best for investors. I have personally seen senior management make decisions that harm the Fidelity bottom line because it's the right thing to do for customers -- and not because they were going to be "found out" but because the first question that everyone has to ask when resolving issues is "what's best for the unitholders?"
Cons
Excessive layering of management. Limited opportunities for non management staff to change tracks within the company. If you're not on the line management track, you'll be basically slotted in where you are and will not be given the opportunity to work in an area that might challenge you or develop skills. if you're on the management track it's a different story, but then you have a whole world of politics to live with.