Shenzhen: China's City of the Future [video]
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It's also very livable. Sub way. Driving, Walking, Biking, Small electric vehicles for short distances. Clean air. No petro smell. Clean streets.
Pretty sure most developed East Asian or even Gulf cities have this. Chinese cities aren't unique in that regard.
If you live in a Chinese city, you technically need to carry your passport around all the time, although I never did. But I wasn’t going to tourist destinations either. I’ve never been to SZ before (just GZ A couple of times), but southern cities are generally more lax than northern cities so if it feels like you need to show a lot there it would be more stressful in Beijing.