Thank you all for the thoughtful replies on this.
Just curious.... how does AA's 789 J product on the Aussie routes compare to the Qantas 789 J product? (hard and soft, but hard concerns me more, particularly on overnight flights.)
I'd have to fly into Sydney for AA metal, but since my first itinerary stop is Tasmania, I'm taking another flight same day from Melbourne anyway. Not a significant difference doing that from Sydney.
I'm intrigued by AA showing they have WI-FI on 789's to Sydney. Last I knew they did not on pacific routes. That would be a serious consideration if so for a 16 hour flight, as Qantas does not. However I can't count on one hand the number of times I've been burned on AA flights claiming to have WI-FI, and either don't have it, or have it but no one knows why it isn't working.