Hi
Would appear Nationwide Debit card may still be the best, even though 1% load applies from July. As you may know in Australia you can freely use your debit card to make purchases or withdraw cash at ATM's. If you have ever been through Australia's border, sometimes they can ask you to provide proof that you have access to sufficient funds for your stay. If you have any proof about payments going into the account connected to your debit card, you would be wise to take this with you. They have been known to refuse entry if they do not believe you have funds to be able to live.
In regard to Credit Cards my understanding is that it is best to buy in Aussie dollars. CC companies often give a better exchange rate, so you sometimes you can benefit, even if charges are involved. Only use the CC the 2nd month you are there as obviously if you use during the 1st month you may not be at home to make payment and incur charges. The current exchange rate I believe is about 1.96 dollars to the pound, so OZ is not a cheap as it was. The last time I went there the rate was about 2.3.
Enjoy your time, you lucky git
Huckster
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