BTW: What are your guys' thoughts on using burner phones vs your 'normal' phone (that you'd use in your home country) in China? I've heard a number of ppl suggest just bringing a 'clean' (very few apps installed, esp social media) burner phone with them to China as opposed to their main/primary device?

I have a couple older devices, a Moto X4 and Moto G6 (both from Google Fi so I *think* they'll work with other carriers/unlocked?), and was considering bringing those and popping a China sim card into both so that my wife and I each have Chinese numbers. I'm not 100% sure yet but we may want to do something similar for my in-laws who will be going there for a longer period of time (3 months). If we do this, should we also bring our primary devices but just have them turned off? Should we expect that the Chinese authorities at the airport will screen these and want everything turned on, inspected, etc?