We have traveled throughout Europe and North America with our son who has c.f. The biggest issue we have had is that his meds and equipment have to have their own suitcase
We have a "Letter of Medical Necessity" which explains c.f. and lists the medications and equipment necessary. Our travel insurance includes health insurance. I would be somewhat concerned about
appropriate medical care if I were traveling in a country where c.f. is uncommon, but I wouldn't worry about
Australia.
We have never had any problems with security or customs.
If you feel well enough to travel, and have cleared the medical/medication issues with your physician, GO FOR IT!
"Life is not a dress rehearsal"