Upvote:2
I think it doesn't matter as long as a bank in Australia has decent rates.
If you decide to do that in Thailand, I suggest you to change a little amount in Australia still and then when you arrive, change the rest in Bangkok because in the airport the rates might not be good.
I recommend Bangkok bank.
Upvote:3
When I traveled to Thailand some years back, I found the best deals where in country! Find a big bank and you will find the best rates, just be cautious about hawkers vending out of date currency! I still have an envelope with a few of the bills I could not exchange back to US currency. They were out of date or fake.