I have seen them in store ( side by side) but on their usual feed. I’ve also watched YouTube comparisons and it’s the reviewers that have made me question the merit of paying £3k more for the A90J.I would imagine if you got the 80J without seeing the 90J you would be very happy with it. See them both side by side maybe not.
I personally when getting something as expensive as this normally want to get the best possible model I can get at the time as I keep them for as long as possible until something that significantly improves things comes out. It would also bug the sh*t out of me that there was a better model haha!
And I agree with your other issue that I also hate the idea of a better model that I could have bought but im trying to be a rational buyer for once!