Daleys Fruit Tree Nursery sells quite a few varieties such as the Soursop Mountain Tree and the Soursop Kyogle Fruit Tree. These selections are grafted and will fruit much quicker and have a proven taste, size and texture that can be a gamble with a seedling tree.
Many people have said that the soursop can be used as a Cancer Cure. Facebook and other Social Media platforms especially have shared this information. A silver bullet like eating one fruit does sound too good to be true however one thing that has been shown time and time again in the fight against cancer is eating a diet high in Fruit, Nut & Vegetables does reduce your risk of getting many common cancers and even when you do get cancer this diet is the one you are often forced to go on.
The variety of fruit that can be grown in Australia is a wonderland with our amazing climate. So a varied diet should be available to everyone by growing fruit trees in your backyard that you can not easily or economically buy in the grocery store. The Soursop would fit this ethos perfectly.
I recommend a grafted variety that costs more initially but produces fruit faster and will likely taste better.