Don't be deceived by the AU and. com.au domain; this is an American company shipping out of Boston, USA and you won't enjoy the protections of the Australian Consumer Law or local shipping/returns. If there is any issue with your order - which my experience and other reviews indicate is common - at best, you will be required to pay return shipping to the USA which is not cost effective. At worst you might end up with a damaged, incorrect, or faulty item, or even nothing at all and no recourse.
I ordered a Military Grade Aluminum Case | Atomic Slim 2 Series case for my Galaxy S10 plus, which shipped the next day and arrived after around a month. On unpacking the case, the clear plastic back had a deep scratch over a centimetre long. The packaging was undamaged, so the damage didn't happen in transit - it was packed and shipped like that. The damage is so severe I suspect the case is a return and not new.
I contacted Punkcase immediately by replying to their shipping confirmation email with the order number and photos of the damaged case. Their form response reply requested the order number and photos, making me suspect this is an automated response. They eventually offered me a replacement, but only if I posted the original case back to them in the USA at my own cost. Since that would cost more than the value of the case, I'm just stuck with a damaged case. So I'd say their customer service is about on par with their quality control.
The case itself is okay, not on the same level as lifeproof, otterbox etc., and far from 'military grade'. The buttons protrude a long way out from the side and snag easily when pocketing the phone. They also have a slightly loose, plasticy feeling and I expect they will be the first point of failure (though to be fair I haven't been using the case so can't really tell how long they'll last). Overall, if I had no issues with my order and the return process, I feel the case is a bit overpriced even with the permanent 'discount' (another breach of the Australian Consumer Law) and would rate the company as 2/5 if they stood by their product by covering return shipping for damaged or incorrect orders.