We have just come back from furnishing our new place I used my Nationwide credit card at Eron Spot on 22 March 08 for £2000 the exchange rate I got with no charges was 2.46 ytl ( in the change shop in Fethiye the same day was 2.43YTL) I made various withdrawals from the cash machines using my debit card through the week and by Friday I got 2.51 no charges ( the change shop and Finnansbank were 2.46 ytl)
I think Nationwide is a great service, saves you carrying lots of money about, and ther cards seem to work ok in all ATM machines. If you use your Credit Card to get cash then I think there is a charge. We both take our debit cards so can withdraw up to £600 per day in Sterling from some ATM machines or YTL