If you have a put money onto on your card as a credit do the cc companies charge for the exchange and withdrawal. I know it used to be the case that they didn't charge once there was a credit/surplus on your card.
When I reserched this -3 years ago now, TSB -ICE, were one of the best for charges when withdrawing abroad. TSB did not charge cash advance fee when account in credit. I had current account with BOI but for some reason, rates/charges etc I went with TSB as package was better then- this was when opened about 3 years ago.