There's a class problem with C2H in almost all companies. Contractors are always seen as less than by management and especially hiring committees. I work at a company that I've been hired thru C2H. Everyone on the team, my manager knew I was one of the strongest programmers on the team. But when it came for my conversion interview I bombed. It was run by 3 of the most senior principles with the lowest acceptance rates and a penchant for "protecting" the company from bad hires. Being told despite amazingly good performance compared to peers you still aren't good enough is a nice little gut punch.
A short time later, I did another conversion interview, got people who were willing to tell me "look, we know you can code" because they had SEEN me code and design systems they were using every day. They still did some interview questions, but lo and behold I didn't feel like jumping out the window every second.