Any australian working in the US that is able to obtain PR or citizenship likely has a well paid job that provides health insurance. While I feel for the folks in the US without coverage, lack of access to affordable health care does not really apply to employed, skilled immigrants. In my experience US health care is the best on the planet, its also the most expensive.
From my perspective, US health care is way above the quality of healthcare in Australia. Price, not so much...
Australia has a very high standard health care system. Probably on a par with the UK and the U.S.
Given that insurance companies will soon be excluding "pre-existing conditions", there's a good chance you can't get insurance under a corporate plan anyway.
From my perspective, US health care is way above the quality of healthcare in Australia. Price, not so much...