NFC works well, and in general with almost 99% of the transactions they are online, with the card validating to the terminal, and the terminal validating to the bank immediately. Offline most of the time NFC will error out, or ask for you to insert the card, and require a PIN entry, so that it can store the transaction for later processing. Here the limit before NFC asks for the PIN is R500, roughly $33US, and pretty much every single merchant rund either NFC or chip and pin.
The only standout is the good old SA Post Office, still using XP as front end processing, and with terminals that have NFC and chip on them (as the old ones wore out and got replaced) that is unused, as the POS application they use has no ability to use those features, so they are still using swipe and PIN for transactions, though of course only for some, as most transactions you need to pay in cash.