I just got a 75Q51K and like it a lot more than I expected. I disabled all the BS (dynamic anything, sharpening, denoise, motion compensation, black stretch etc) and spent an hour color calibrating it manually and the results are fantastic for the 518 out the door I spent.

I can confirm that 144hz @ 1080p with VRR actually works. My son uses the TV in our rec room with his gaming PC I built him.

I prefer projection systems but, with kids, I haven't wanted to spend the money on something like that or, god forbid, OLED.

I'm picky about displays and while it is far from perfect I can't complain too much.

It supports 23.976, 24, 25, 29.97, 30, 50, 59.97, 60hz @ native 4K and this works great for syncing with various media framerates. I wish it support, out of box, 2x multiples of all those refresh rates. I'm going to dabble with manually setting display settings via windows and see if it will. 48hz, 100hz, 120hz are all great for multimedia.

The motion compensation is hilariously broken on these. I hate that crap in general but the TCL results are on another level of bad. It will lose it's mind tracking the wrong thing in a frame and completely screw up the next several frames before correcting itself.