PubNub uses Points of Presence closest to client locations to minimize latency but we do not have a PoP within China. Due to China's firewall, connectivity and latency may vary per use case, however, PubNub has many customers that have users inside of China and operate with no to minimal network issues.

We recommend performing some minimal testing with your PubNub POC application and before you expand that to increased throughput/stress testing. 

Please contact PubNub Support for further guidance.