When I was ready to leave my legacy job in the US over 4 years ago I saw a advertisement for VOR in our flight ops. It was started by somebody from my company in the US with a Chinese partner. Over several emails and conversations, including them demanding that I sign an exclusive contract with them for any contract in China, I realized they were sheisters and stopped talking to them. I never could get a straight answer from them about taxes. Every time I asked I got a different answer.

Fast forward 4 years. I just finished a 2 year contract in China. VOR has a bad rep, and very few pilots on contract. There are far better choices in China. I would recommend Parc Aviation and Wasinc.
I was with Parc, and they are first rate.