Pros
The work is very easy. This means there isn't a high bar when it comes for looking qualified applicants for most jobs. Most of FSA's positions are great for someone looking for their first job. There's very high turnover in most of their contracts, so there is usually always positions open.
Cons
The jobs are not very technical, so you likely won't be learning any new skills to bring to other jobs. They hide the policy on vacation and look for every possible way to not pay it out. The specific policy on vacation leave is not in the employee handbook, but instead referenced to a separate document. My boss didn't even understand it correctly and told me I would get vacation leave cashed out for my 9 months working when it turns out you need to have worked for 1 year before getting any leave. Another one of my coworker's was leaving the job because she was deploying with the Army, but FSA wouldn't grant her 3 days of leave without pay so she could hit her 1 year point and earn that vacation leave.