If I were to do China I again, I would only do it based in Beijing, Shanghai, Guangzhou, or Shenzhen. That is it.
Why? Access to decent western healthcare. Where I was based the last year there was none. We had to hop on a plane to somewhere with a decent hospital.
In 12 months (5 pilots):
1. One medivac-ed out due to injury.
2. Same pilot self-medivac-ed out due to illness (2 weeks in hospital).
3. 2 other pilots wish they had flown our due to illness (also 2 weeks violently ill)
4. The other two (including me) all flew to Guangzhou at least once during that time for medical attention.
Tianjin is close to Beijing, but not close enough. Still a couple of hours by train or taxi.