Pros
The benefits of working here really depend on the contract you're working under. There are some interesting projects - including mine - that can be really professionally rewarding, and many of the non-managerial people, at least that I work with, are engaged and motivated. I think the higher your level of expertise, the more worthwhile it would be working for this contractor. The more specialized your knowledge, and therefore the more control you have over your work assignments, the better. If you're just one of the rank and file, then the situation would be very different.
Cons
There is very little good to say about the company itself. They don't really *do* anything, they hire people to do things and then scoop off a portion of everyone's salary. That's how contracting works. CSC is in the middle of an attempted turnaround, having hired a CEO to goose their stock price (and his compensation is based on annual percent gains in stock price), and they've been doing this primarily by improving margins by cutting benefits and by pushing everyone to go out and get more business, in addition to doing your actual job. The list of indignities employees have had to put up with in the past few years is too extensive to list, but includes a Draconian (and nonsensical) assessment/wage increase policy, constant changes in health benefits, changes to vacation policy (aimed at getting vacation days off the books and thus forcing employees to take vacations on specified days and reducing vacation accumulation and carryover). There has been much disaffection amongst the ranks, and I know a number of people who have either left or are actively looking for ways out. I get the feeling that there's little room for advancement, and there's pretty much a cap on salaries these days, and there's very little support (or tolerance!) for professional growth within the company. I'm pretty much outside of all of this because of the highly specialized nature of my work, but still the general malaise is hard to ignore. Bottom line is that unless there is specific work on a specific contract that you're really like to be doing, you probably don't want to work here.