Using a card in US is quite disconcerting given the variety of ways in which you are required to use your card (insert in machine, swipe at side of machine, tap etc), the number of ways you validate (enter PIN, sign check, sign mini screen etc), that carry on in restaurants where they walk off with your card and return 5 mins later, the open tab (to allow you to write in a tip on the check after the card has been processed) and the huge number of places that won't accept ApplePay/GooglePay. On my last few trips I've limited myself to my N26 card on the basis that I get instant notification of all transactions to my phone and watch. I'd be reluctant to carry any card that didn't offer instant notification (reliably, looking at you AIB) in the US.