I have the 55" and here are my thoughts and some insight since everyone's attention seems to be on the 65". I am primarily using it with a PC for gaming & PS4. Calibrated it with an i1 (150% sRGB/95% DCI-P3) and out the box it's actually very accurate in the "Low" color preset which is closest to 6500K white.
The Panel itself:
-Corners and edges are yellow (doesn't bother me).
-Moderate DSE but much cleaner than any of the TCL R617's I tried. Comparable to Q8FN/P55-F1.
-No pixel dithering/BGR
-Overall black levels with FALD off are very impressive as is black uniformity.
-Does 1080p/120hz via forced resolution using CRU. 1440p/120hz is accepted but it only displays it at 60hz (maybe firmware update required).
-Is extremely aggressive even on lower settings and can not keep up with fast movement but I've only seen this have any real world impact on test videos. Real world it's not a issue.
-Zone transitions are not as smooth as Samsung/Sony but it's not a big deal.
-Subtitles will cause the typical FALD "bloom" as they come and go.
-Overall the zone count (10x10 = 100) compensates for it's inferior algorithm compared to the Q8FN I had.
What I hate:
-The software is a buggy/busted mess. The TV did 2 firmware updates on it's own within an hour of powering on. Sometimes my settings reset, sometimes I get crazy input lag and need to switch out and back into game mode, etc. It's just not a polished experience right now.
-The backlight/brightness control is convoluted and dumb. With local dimming enabled, the TV will not allow you to adjust backlight. You have to disable it and then have access to backlight setting, change as desired and then re enable local dimming. Seems like they really want you to use the light sensor.
-Insane amount of overshoot/inverse ghosting. Hisense went nuts with the pixel overdrive for dark transitions. Playing any game with dark content results in disgusting inverse ghosting everywhere.
If I used this TV strictly for media consumption (Movies, shows, etc), it's a keeper. HDR performance is impressive as is color. The TV has some of the blackest blacks I've seen in a while. Since I'm primarily a gamer the deal breaker is the inverse ghosting/overshoot and as a result I will be returning it. I don't want to discourage people because not everyone will even notice it but once it's seen it can't be unseen. Also, I really don't want to wait for Hisense to get the software together.