Pros
I was able to work for a Fortune 500 company, as a contractor, which was a great experience. The other guys on my team were great and I really liked our SIM (who we reported to since we didn't have a Team Lead on site). Benefits weren't bad, I'd say they were on par with other companies I have worked for.
Cons
I did not receive a raise during the time I was employed by CompuCom. I took on more responsibilities, advanced in position, created tools used across multiple sites, and had a great annual review but none of that translated into CompuCom valuing me any more then when I just was starting with them. Based on other reviews and from what I have heard about from others it sounds like the situation I was in was far more common then it should be.