Melbourne

I got my XM3 cans May 2019 and they're still going great. Somewhat grotty as I also use them as ear muffs, eg chainsawing and wood chipping. I've probably used them at minimum 4h a day 4 days a week in that time. Still finish the day with about 50% charge left in them. The XM5s don't fold down which could be a travel concern but I haven't actually folded my xm3s away very often. I went to Amsterdam for a few months so used the case on the plane. I have a big head so tend to prop them above my ears as required, vs my friends wife who can wear them as a bit of a necklace. I see the XM5s on sale on ozbargain pretty often.

1. Claiming things on tax really depends on which tax bracket you're paying. eg, I'd only be getting 30% back because I don't earn a lot. If you're paying 47% tax it's a bigger discount.
2. Ew, not for me.
3. I'd probably do this personally, you can still claim the XM5s on tax.
4. Ew.

I'd consider Airpods Pro Gen 2 as I hear great reviews of them, also mum's going a bit deaf but is too tight to buy herself some, I could palm them off to her as hearing aids.

The sony cans can get hot in summer, I also have an Aftershokx bone conduction headset which are great in the heat, but don't "block" any sound as they keep my ear canals open - for cycling.