While I love the Chase Sapphire Preferred, I have had difficulty using it recently - most recently last week in London and in May in southern Spain.

While most vendors do have a card reader, I have found that on several occasions, the "thickness" of the card has made it difficult for it to slide through the reader on the sides of the machines and the vendors need convincing to "try it again" and get the speed right.

Some are "concerned" that there are no raised numbers and have refused to even try it.

On the other hand, when it works, it has worked flawlessly and the exchange rate was very good (with no Forex fees too )