_The cost of living?
According to www.expatistan.com, the cost of living in Chengdu is 18% cheaper overall than Datong. A month of rent for a furnished 85m2 apartment is 5,000 chinese yuan, and it is very cheap for a furnished 85m2 apartment.
Wondering which university that your cute children will go to? Go to Chengdu for 30+ universities waiting for your child, and 20+ international K-12 schools in the area. Datong only has schools that the government built, and one of the schools in the area is built by the big coal mine company. It is at a very poor condition, and the education there, is not recommended by the local people, according to google maps reviews about the place.
So this is pretty much it!
Reasons why the climate and food in Chengdu and Datong weren't listed? Because the two cities have nearly the same climate, which is a humid and fairly cool climate all year long. The local food actually didn't matter, because we aren't going to be going outside to eat meals every single day.
-SOURCES AND WEBSITES: https://www.expatistan.com/cost-of-living/comparison/datong/chengdu?https://namu.wiki/w/%EC%93%B0%EC%B4%A8%20%EC%84%B1?from=%EC%93%B0%EC%B4%A8https://earthquaketrack.com/p/china/sichuan/recent?before=2015-12-10+21%3A27%3A45+UTChttps://earthquaketrack.com/cn-24-datong/recenthttps://www.international-schools-database.comhttps://www.chinahighlights.comhttps://www.travelchinaguide.com/climate/chengdu.htmhttps://www.chinahighlights.com/datong/weather.htmhttps://www.chinahighlights.com/sichuan/weather.htmhttps://namu.wiki/w/%EB%8F%84%EA%B0%95%EC%96%B8https://namu.wiki/w/%EC%B2%AD%EB%91%90http://news.xinhuanet.com/english/2015-11/23/c_134846806.htmhttps://www.google.com.hk/search?q=datong+earthquake+proof+buildings&rlz=1C5CHFA_enCN706CN706&oq=datong+earthquake+proof+buildings&aqs=chrome..69i57.10196j0j1&sourceid=chrome&ie=UTF-8https://www.travelchinaguide.com/cityguides/chengdu.htmhttps://www.chinahighlights.com/datong/map.htm