Absolute rubbish Jimbo, you're getting it completely wrong, you're suggesting buying euros with a "no commission" credit card BEFORE you go abroad, which is obviously not the thing to do. Clearly the rates will be rubbish as you say.
I'm saying simply pay by a " no commission" credit card when you make a purchase abroad, that's the whole idea of them!
Check the independent financial websites, they'll all tell you the same.
Much as it pleases me to disagree with Jimbo, the following applies:
1 Loose all your euros and they're all gone, loose your card or pre-paid card and you can get it stopped and replaced quickly (see Gav's posting)
2 Almost all taverna's take cards, the exceptions are well known
3 Of course you wouldn't expect to pay by card for a couple of beers, I carry euros for many small purchases and for taverna's that don't take cards, but for larger bills the no commission cards come into their own.
4 Take sterling and exchange it in Ag Stef and you're going to be a loser (see below)
5 I don't know who the "doughnut" man is but I'm getting a good idea!
In June 2013 the exchange rate at San Stefanos Travel was 1.15 before commission, so 1.127 after commission.
Paying by Halifax Clarity no commission credit card in June 2013 gave a rate of 1.18 to 1.19 over a period of two weeks.
If, at that time, you had exchanged £1000 worth of euros in resort (San Stef Travel or others) as you have suggested, compared to using a Halifax Clarity "no commission" credit card in resort you'd have lost between 53-63 euros.
Need I say more?
You take your sterling Jim and I'll take my "no commission" credit cards, it's clear who'll be the winner.
Do your homework Jim!!