Avantages
Easy and fast hiring. They'll fly you out and house you wherever they're doing training at the time. They'll be paying you while also giving you a stipend. This is great as a right-out-of college job. They offer paid learning time while not on an assignment. If you've got good individual drive, you can get paid to learn a new skill that will make you marketable.
Inconvénients
Opaquely bureaucratic as heck. Out of our hiring group, half of us got assignments within a month, the other half waited about half a year before they got any work. At the same time, half of us on-project didn't get a promised minor pay-raise and promotion until 4 months after it was promised, while about half of the folks on bench got it. No matter what subject you interview with, they'll choose your job position for you. I interviewed with SQL knowledge and got thrown into web automation testing training based entirely on the hire date I chose. Nepotism runs rampant. Many of the managers you work for and people you work with have no clue what they're doing. It's entirely hit or miss as to whether your manager cares and knows what they're doing or if they're petty, demanding, and micromanaging. There's this clash between a stated goal of hard work and continual learning and the reality of apathy in many places. Overall, the place is soul-draining. If you've got a good work ethic, pass this company up if you can. You'll find better work and pay elsewhere