Edit 22:45: Small out of stock at MYER, however few remaining of the larger size below.
For those that missed out on the AmazonAU deal that has now been marked out of stock.
Reposting results of my insulation testing:
Insulation test: https://files.ozbargain.com.au/upload/143600/122380/screensh…
Regarding insulation capabilities - overall not bad at all, on par with my Frank Green stainless steel insulated one and much better than similar plastic or glass reusable cups. All cups started with 250ml of 91˚C water within them, ambient temperature 23˚C (so differences may be even greater in colder environments).
(Large) Stainless Steel 454ml:
https://www.myer.com.au/p/joseph-joseph-sipp-stel-travel-mug…
Also available for $1 more on the Joseph Joseph website but $12 shipping for orders under $80 probably kills the deal.
Still looking for deals on dishwasher safe mugs… (though I've seen plenty go through the dishwasher fine).
So far I've only seen YETI insulated stuff advertised as dishwasher safe. But since one (fairly big name) brand can do it I don't see why there aren't more options :-/