http://www.moneysavingexpert.com/tra...p-travel-money
I have Nationwide credit and debit cards solely for use abroad. I find the most useful feature is being able to take cash from an ATM as I need it, rather than bulking up to lower the fixed fee.
Also - I have around 100GBP in Euro and Dollar travellers cheques for emergencies - once in the past five years I've been unable to get cash from the ATM when I landed. You may prefer to ensure you have 100GBP in cash to change on arrival
in an emergency only.