I think it's a lucky dip and if they like you or not Rob. Often payment methods depend on the type of delivery that is being used. When I had my G11 sent from OPT I simply got a phone call from the shipping comp here in Aus saying that Customs wouldn't release it until the GST and Duties were paid. I paid and everything turned up fine, np. But I do know others have had a nightmare of a time with it.
Have you checked out this
Customs site?