In money % spent, I'd say about 2-1 (in favour of Amex) - a hotel night costs roughly 500 RMB (I like good 4* or 5*, depending on locations, and we all know the little tricks here on FT to get such rates ) in average, that expenses can be paid by Amex.

I've had a few stays in hotels which don't take Amex or even MC/Visa (usually they either take all, or none), but for those I can always use an ATM or UnionPay.

Other expenses, unless I go for expensive food (seldom) or "expensive" shopping (even more seldom), 200-300 RMB is more than enough for what I spend on food/transport etc. - obviously being almost only in Cash or UnionPay (debit card). So, while the amount of transactions that I'll be using my Amex is low (1 transaction per stay.. but then, China is a GREAT place to get some stays for brands like Hilton ) the amount is high compared to my other expenses, which are plentiful but low.

So, for many transactions I'll use cash as it's fast and easy (sure, contactless is faster.. and I love it in places like Singapore or Switzerland.. but it just won't get on in China I've the feeling..) - and for those few hotel (or expensive restaurants) payments, I'll go with Amex.