Vantaggi
They pay you as a full time employee while training you in Full Stack Development or Data Analyst. They provide lots of material for upskilling post training as well. They also teach/train you in soft skills to overcome all interviewing challenges. They have a large variety of clients and try to fit you with the right one and are constantly selling their consultants to clients in hopes of placing them somewhere, with a contract that can lead to full time placement (ultimate goal).
Svantaggi
If many companies are in a hiring freeze (for whatever reasons), you might be "on the bench" in the Work Ready Consultant team waiting for placement. (though they keep you busy learning and working on your skills) Lots of redundant reporting of what you did each week that gets tiresome.