Pros
There is no micro management. Onsite cafeteria. Quiet work environment. Those who are self-disciplined can definitely improve their skills. Nice location in DC with shuttles to the nearest metro stations. Really the only part about ARC that impressed me was their commitment to diversity, with regular meetings for employees who wanted to attend.
Cons
Somewhere in the organization there is trouble transitioning to technology. They use the same checks and balances they probably had in place before email, internet, etc. It's quiet and very very lonely. The only people I regularly spoke to were two people sitting near me, and the people I met smoking outside. On my first day I was given a brief tour, a desk, a computer and a phone. I had computer trouble the entire time I worked for them. My computer was so slow that adding a row in Excel could take up to twenty minutes. From what I saw, my only guess is that managers have just been promoted based on their time with the organization and not based on their skills.