I have a starling card for using in Spain, I'm going next week. The XR for starling today is 1.162 Pounds to Euro and depending how and where I use it I might not get charged anything. Starling don't usually charge transaction fees but other banks whose Atms you use do, Atms for Deutsch bank in Spain don't charge Starling cards, alternatively if I was daft enough to use a Santander ATM I would get shafted, it could be around 10%, its worth checking expat sites for the country you are going to to see which banks charge and those that do not. Unlike Revulut or Monzo I can take out more cash without incurring fees, but I might get charged like they do for doing it at weekends.