I had a very negative experience with these recruiters. They called me to the side as I was walking by at a campus job fair, and started asking me technical questions before even asking for my name or resume. After a few, they put me down for an interview. The recruiters then showed up 30 minutes late to the interview, and the actual questions themselves were a nightmare. They asked me stuff that just wasn't feasible to write as code for an interview question, and I somehow made it through the first round and had to come back the next day. They were late once again, and the process repeated. They seemed to get extremely frustrated when I couldn't write the implementation to an entire threadpool in C on the spot. That's not even an exaggeration, it was the first question they asked me.