Pros: standard employee benefits. vacation, sick time, health insurance, etc. and after a waiting period, a little money to buy job related books.
Cons: being dumped at a customer location by yourself, without support or backup. you're on your own, pal. no job security.
All they care about is the money they can make off of you.
If you are a consultant, they will pay you a little as possible and usually will charge the clients you will be working at 2 to 3 times what you are paid.
They pay a lot of lip service to "career advancement" but that is all it is, lip service. If they have an assignment that they want to put you in, that is where you will go, regardless of what it is you want to do. And once in an assignment, if the client is satisfied with you, it is very difficult to get out of it. People get stuck doing jobs they don't want for years, with no way out other than to quit. But on the other hand, if the assignment you are on comes to an end, and they don't have anything the can put you in at that time, you are history.
They offer very little training (in-house only) and what the do offer is not very good and on your own time.
If you are desperate for a job, this place is will do until you can find something better.