Rikki,
I think that you, like I did, should pay only the upgrade to the Super Pak to have all the 20 Real Drums sets. The price for the upgrade is just 79 USD and you can download all the files from the PG Music website. The shipment to Europe by ordinary mail costs another 10 dollars, but maybe to Australia is more than that.
So, what can I say? The Terry Clark styles really rock and I can see them being the fundament for many PA2 styles... besides if you buy BIAB 2008 you will receive also the Real Tracks package, including real guitars and also a real saxophone; I don't know if that is included in Power Tracks as well.
I will let you know more in the next few days, as I learn more about the program.