They don't like to hire people as full-time employees because they're cheapskates and don't want to give you benefits or any other security. They just string you along as an independent contractor.
It was hard to get paid. They would delay payment to contractors and make me invoice them for every paycheck...and I worked solely for them 40hrs a week for almost 2 years...
They thrive off of the "do it really quick and crappy because our customers don't know any better" model. They didn't care about quality because they are in a niche market and all their customers are bureaucratic organizations.
They are 10 years behind the curve of the 3D Industry, so everything you make for them is worthless for your portfolio.