ICBC cards are known not to be able to be linked to Amaze since Day 1
Noted with thanks.
Can use Amaze for anything be it locally/overseas, online/offline.
Main point is can earn points/cashback on the linked card e.g. 10x points on Citi rewards mastercard, and no foreign currency fee or cross border fee. The 0.5%/1% Amaze rebate is a bonus if meet the $1500 quarterly spend.
Typically should choose to pay in local currency to avoid dcc.
The only Mastercard credit card I have is the OCBC Titanium Rewards which offers OCBC$ in blocks of $5 (not worth considering).
Nevertheless, are you saying linking it to the Amaze card and paying in USD/GBP for my iHerb/Myprotein purchases is cheaper than converting to SGD and charging to my HSBC VISA credit card which gives about 1.5% (1.5% + 1% - 1% DCC fee) net cashback on SGD transactions?