G'day J.D,
I am from Aus and I bought my Iwata HP-C (which I love by the way) from Dixie Art. I also ordered some extra bits as well while I was there.
No, I did not pay any customs duty on it when it was shipped.
The prices at Dixie Art are extremley good, even with the postage costs thrown in. The way Dixie art works is that once you except the order they will go away and figure out what the shipping costs are. These costs are then sent to you in an email and you can choose not to continue with the order if you wish.
My ab arrived very promptly after I confirmed the order and shipping costs. The only delay was in receving the confirmation email from Dixie Art which took a while.
I would not hesitate to use them again for another purchase.
Hope this helps
Darren