Originally Posted by mntblue

OP wants to enter mainland China with PRC passport and leave with EU passport. The risk is that exit control will check his entry stamp on the EU passport. No entry stamp no exit.

If the OP uses his PRC passport to exit, he needs a valid visa. (Yes there are a few countries mainland Chinese can go without visa, but somehow the exit control guys don't seem to care)

I'm not familiar with the rules governing HK/TW id. I assume it's much easier as you basically have dual citizenship with two entities other than PRC.