I have seen customers using our service in China for sure. However, there are some things you should be aware of
We have seen some speed issues with customers based in the Asia-Pacific region with our platform due to ISP problems connecting to the AWS CDN as well as geographical latency.
Blocks put in place to sites outside of China will also vary from provider to provider.
You can check the latency to AWS us-east-1 here: Cloud Ping.
We currently host our platform entirely in this us-east-1 region.
While we do use other caching services that are more dispersed I would suggest contacting your ISP and check if they have any issues connecting to this datacenter.
Let me know if you have any questions about that