Pros
They will make sure you get the job. Even hand you the questions that will most likely be asked in the interview.
Cons
Once you are in you are just a pay check to them expect zero support or raises. took me two months to get a response. Even after finally getting someone to return my call I said "Raise" and they ghosted me for the next two weeks. I asked about holidays and there answer was simple "No work, No pay" so holiday season hurts since there are so many forced days off without pay. Also you can work on those days or use a sick/vacation day to cover those hours. also they will low ball you on your pay. give you some we max this position out at X when in reality that is less then 40% of what they are charging the company that is gonna contract you. also the benefits are pure trash basic or high deductible. basic covers preventive care so nothing really that would cost you much no ER or surgeries. The high deductible one is spend 6 grand then they will start to cover the non preventive stuff. so if you are planing on break multiple bones and have a healthy 6 grand burning in your pocket pick that plan. that is it. they will say every position is contract to higher knowing full well that the company that will contract you has never hired a contractor.