There are some new burners out recently that have attracted a lot of attention from the members here. Whether they are available in Australia is another question entirely.
You should look at the threads discussing the new NEC/Optiarc drives...the 7240a/s and the two new Pioneer drives, the 117 and the 217.
Here is the results thread for the Pioneer 117D: http://club.cdfreaks.com/f87/pioneer-dvr-117d-results-discussion-270005/
Here is the discussion regarding the Sony Optiarc/NEC 7240: http://club.cdfreaks.com/f86/optiarc-ad-7240a-s-results-discussion-269788/
Be warned, this one goes on for 5 pages.
You don't mention whether or not you can use a SATA interface drive or not. These come in both SATA and the older style IDE/PATA, but may not be both available here in the US yet. I have no idea on lag time for arrival in Australia.
I don't keep up with Asus drives personally, so I'll let someone else discuss them with you.
Welcome to the forums.