"note that Samsung and Sony share LCD panels due to their production joint venture"
But also note that while there are only a few manufacturers of panels, there can be a big difference in the electronics driving them, which can make a big difference in picture quality, features, and ease of use. IMO Sony's electronics are probably better, but I haven't looked at Samsung's products or read any reviews lately, so they may have come up in the world.
Seeing the Sony and Samsung side by side, they appeared to be very close in performance with a slight edge to Sony, but I'm not sure it's worth the attitional ~$1k difference in price for the Sony, though.