Pros
It is owned by Berkshire Hathaway which provides some stability. Overall, the benefits are small in comparison with the drawbacks. If you are interested in working there I would recommend you do extensive research to make sure you are placing yourself in a "workable" business unit. Corporate in Virginia seems to the best choice within the company as far as managerial and cultural dynamics. Your experience can vary widely because the company is very fragmented. They offer an interesting commuter tax shelter if you spend a lot on parking, train, or bus transportation. If you drive to work and do not pay for parking then the system has no advantages as gas is not a qualified expense.
Cons
Overall the largest drawback is a lack of vision, communication, direction, and skilled management. The company seems to have an identity crisis and is unsure of what services it wants to offer. Business units are often completely oblivious to each other and may even deny affiliation with another unit simply because they have not been informed of it's existence. Many of the positions have no written job description and I found that you are often heavily assigned "extra" projects that have no relevance to your job title. Their internal billing system causes a lot of customer dissatisfaction which is becoming a point of customer loss for the whole company. The benefits package is not competitive.