Pros
There is something to be said for working at a corporate headquarters location. The office facilities are very nice and it is helpful to be located in a central office where it is easier to interact with other employees and network. That said, it is a much more formal work environment which can take some getting used to-formal dress, formal interactions, formal management structure. As anywhere, depending on who your management is, this can be a good thing as there is a big emphasis on the review process. If your management is supportive and willing to weigh in on your performance in a positive light, it seems much more likely that your efforts will be recognized.
Cons
The setup of behind the scenes support- finance, contracts, subcontracts, is less than ideal. They are trying to accomplish across the company support (since these are overhead functions), but it often backfires in that there is no way to get ahead if you are not on the front lines of "client staff", nevermind that client staff would not be able to function without GO Team support. Now, with the Carlyle group buying a controlling share of the company, there is ever more emphasis on increasing profit-bad news if you are performing a support function for the company.