They are the Factory or Supermarket to the world. Cheap things come from there. We need $10 for 1 gh/s or less.
Go with the cheapest of course,
but don't support anyone who mines on anything but testnet. KNC has claimed they won't mine with what they develop.
Please think it through. To say otherwise means you don't understand how the growing hashrate and difficulty works against small miners. You will only be hurting yourself.
You will make less for yourself @ $17 GH if they are also developing hardware to mine for themselves than with someone @ $17.50 GH who only uses testnet and isn't mining with your hardware. End of story.
Do not support China.