I have banked with the nationwide for years.
There are at least 2 types of credit cards. One offers cash back. I have that one as I clear my balance each month. They offer 1/2% on everything you spend. When you first join I think from memory you get 2% for the first 6 months. Until March of this year, you use to get 1% cash back, but obviously people like me were spending too much, and clearing their balances each month, so they didn't make any money. You get the cash back added to your statement at the end of December. Watch the interest rate on this one though if you don't clear your balance.
The other one is a normal credit card, no fancy things attached, but lower interest rates if you don't clear you balance monthly.
The Nationwide Flexaccount, is a normal bank account. They are great if you overdrawn on a regular basis, if you go overdrawn. You only pay interest for the time you are actually overdrawn. For example last month, I was overdrawn for around 2 weeks to the tune of £300.00 (paid the credit card off as usual), and I had to pay interest of around 0.50p. No charges for cheques etc like some of the other banks.
Anyway, I used my credit card to buy some tickets from the US in Nov 2004, when I checked my statement, they had given me the official bank rate for the transaction, and not the tourist rate. So if you spent something on your card today, you would get around 1.91. Great or what.
I have bought some dollars, but the rest will go on my credit card, and I will pay it off when I come home.
Happy shopping.
P.S. In case you were woundering, I don't work for the Nationwide, I just spend lots of money I don't have, and have found a bank that doesn't charge a lot for going overdrawn on a regular basis. I actual work for the Government. Someone has to