I worked as an English teacher in China for a decade. It's a wonderful place to live, but not an easy place to stay.

Firstly, you won't get a decent job unless you're white and from a small range of western countries like the UK, US, Canada, Australia, NZ.

Secondly, even if you qualify you'll have to renew your visa yearly and after 5 consecutive years it gets increasingly difficult to get renewed.

Thirdly, going home can be hard. You will have to go home eventually, unless the Chinese government starts giving out more greencards. I lived in a tier 3 city, and in 10 years I only knew of one guy from the UK getting a greencard, and his father-in-law had comnections in government to make that happen.

But if you meet the conditions and can handle uprooting your life at least twice, I'd recommend it.