Im on a working holiday visa and got mine changed, I would rather pay a couple of hundred bucks for a licence than risk the huge $6000 fine if you get caught with an English one when you should have an aussie one. I was told you can only drive on English one for 90 days, weather you are a temporary resident or not.
It is so easy to get an aussie one, all you have to do it go into the rego centre, show both parts of your English licence, pay the fee, get you photo taken and licence will be in the post to you. You keep your English one and there is no tests.
Also you cant use your English licence as ID