I'd be interested in a comparison of what a UK bank charge is for say withdrawl of €500 from a hole in the wall in Mallorca, compared with what commissions are taken if you exchange cash at a travelex or some other exchanger, or one of those prepaid "no fees" travel cards... I'd bet they aren't that different, really.
Here's what makes me question this:
The bank rate today is 1.23235 Euros to the Pound. On the street that means you'll get around 1.20, or a good rate would be 1.21. At the end of the day, that comes to about 3-4% commission.
If you take the time to search and buy one of those special prepaid travel debit cards which has "no fees" and you pay 1.21 exchange rate, then you're still paying at least 3%.
By the way - "no fees" is simply impossible in all ATMs - banks don't spend €50K to install an ATM because they are "nice". It's a profit center. Any ATM not from the card's bank, or carrying a special agreement with the card issuer - will charge some kind of fee - sometimes a lot. And Travelex or any other card issuer can't possible have agreements with all ATM owners. Simply not possible. There will be some ATMs that will not charge, but many will. Some will be criminal about it.
OK, next ... so if you withdraw €500 at the most expensive hole in the wall you can find using your regular UK debit card, and get charged €20 in fees in total (that's a lot!), that's about 4%.
So, I have to question whether taking the time to find the "best" exchanger or finding the "best" prepaid card is really worth it. At the end of the day, I reckon the charges are about the same...