Pros
In my division, there are a handful of smart people and lots of people who are passionate about cyber security. If you love cyber security so much that you'll by happy to work on it late into the night, you'll find a natural home at FireEye. Compensation is very good (salary and bonuses). (However, you should know that some bonuses are provided in the form of stock, and the stock isn't worth much.)
Cons
My division reorganized three times in less than a year. Acquisitions cause lots of turmoil and when they happen so often, teams barely have enough time to get reorganized and never really operate with any kind of efficiency. Managers are extremely inexperienced, and often young (20s...) and tentative. They have no idea how to manage people because they've never done it before, and since most of them fall into that boat, there's no one they can look to as a mentor. Not a single manager in my entire division has a mission statement much less a goal. The end result is that employees spend a lot of time floundering around trying to figure out what their role is. The corporate leadership has only one goal: raise the stock price. Integrity and quality are not really valued here.