This is probably more of a financial than medical question – as it depends on your income and the rebate from government. But from a health perspective, what insurance gets you is access to private hospitals (plus extras – but again, you decide on those based on your finances and need). Private hospitals are great for NON life threatening things like less-major surgery, fixing up chronic medical conditions, getting various treatments that are expected to go well etc. You get fancier facilities, better food, & choice of doctor. If your illness is life threatening I think public is better. There are more staff (& usually less ‘agency’ or temporary staff), better night coverage, bigger ICUs, & access to more specialists if other opinions are needed. Also I think public has better protocols for care, so in my opinion less mistakes are made and your more likely to get evidence based opinions rather than one doctors view. Public clinicians (doctors and nurses) work in teams. To be fair, my opinion isn’t universal – some in private disagree!
BUT for mental health, I think the private system has some distinct advantages – and I DO NOT work in private psych (so I don’t think this is a biased view). The advantages are that it is FAR easier to get admitted when you need it. The public mental health system is area based (so you must go where you area dictates, regardless of whether it is has a good reputation), and it is a bit overcrowded, so it’s hard to get admitted unless you are very unwell (usually that means suicidal). If you have a chronic condition, or are at risk of one (things that put you at risk – past psych problems or past trauma or a family history of psych probs) then I’d get private insurance just to be safe and to give me choice around future admissions. I’m not saying the public system is bad, but it is not as well funded as the public general health system. For psych, the lack of decent public funding means less beds, and useful less adds on’s (like group therapy, psychology programs etc) compared to the private system. Sad, but true.
So in summary: for general health, get it if you can afford it, but the public system is perfectly fine. For psych problems, I think having private insurance is a distinct advantage.
Hope this helps.