Pros
There are many people to help you succeed:
- you get an account manager to find new assignments. They have a good network and know many companies. You work together with them to get an assignment that suits you.
- you get a field-manager to help you stay focussed, get connected to other developers, talk about issues with the assignment
- Nice community, with knowledge sharing
- Great salary
Cons
- they take quite some money (45K annually) from your hourly rate, while not having many extra perks;
- the assignments are not always a good match
- going from assignment to assignment