Pros
The people you work with are some of the best around. They are responsible, dedicated, and all-around decent people. You get a lot of responsibility very quickly, which coming out of college is something that you won't get everywhere. That can be a bit of a double-edged sword, but if you can handle it, then you learn a lot in a very short time.
Cons
The overall culture is very much "get your work done, whatever it takes". Early on, that's manageable, but they will seemingly keep on adding responsibility until you cannot handle it anymore. Then you generally leave, or they back off because you've demonstrated enough value that they will do a good bit to keep you. Because of the nature of the business (fluctuating project numbers) they will work very hard to ensure that they do not over hire, which can guarantee that you'll end up with as much as if not more than you can handle. The travel schedule can get daunting, especially if you have multiple customers, so you won't likely be home except on weekends. The business is also client service, so if you end up with a customer you don't get along with, you've got to stick it out until the end, unless they request you get taken off, which reflects badly on you.