Got the 83" G4 onto wall without any major dramas, and was relieved I could get it to the perfect height on my old bracket without having to move the mounting plate (I really didn't want to get the power tools out again!).
It's a whopper. The box is enormous, and TV is heavier than I was expecting at about twice the weight of the 65" C8 it replaced.
Haven't had a chance to watch much yet, but initial impression is (unsurprisingly) that it's a very nice TV if you can justify the spend.