I have a Samsung Vibrant on T-Mobile and it has been great for tethering/proxy support. The ability is built into the phone and very easy to use. The only down side with T-Mobile is they will slow your connection when you get within a certain amount of data usage. We've used this ability to link the laptop and keep the kids busy while on the road. It's one of my favorite features of the phone and android. I've had the phone for a while, but Samsung has a new phone available which looks really good. I would assume that tethering would work on it as well.
China's just the sucker that gets caught doing it. They're after all sorts of targets, government or otherwise. I had them ruin my. Xmas holiday when they tried unsuccessfully to send 10G DDoS attacks across the wire. Just protect your stuff, because there are a lot of people out the with a lot of motivation to either get your IP, money, are just try to shut you down. China's just one of many. If you have any sort of online presence you are a potential target.