OEM is by TCL . But Panasonic is the one who finetune and tweak it .
It just goes to show 1 thing , when it comes to accuracy (hence , PQ ) no one has surpass Panasonic and their can do it on any platform given the resources .
The only reason they tripped last year , was due to the limitation of the crappy TV CPU .
Otherwise , Panasonic TV is always a pleasure to watch .

I probably have mentioned this before  , watching anything on the these Panasonic OLED is like looking at a piece of  smooth and silky fabric  .
It is eye-wateringly beautiful .

I just wish they get rid of the crappy " myhomescreen " UI . It has been pulling their legs for so very long .

Currently I still have a C7 , a C8 and a CX . All of them have over a thousand of hours watched .
I also have an old A9F I bought from Sony at really cheap price which I am using for color workflow .
Obviously I am a TV dork , so I don't just watch TVs .
I run patterns on them , I tweak them over and over to find my settings and even subbed to most of the major streaming platforms just to stream things on them .
It is just a hobby of mine .

I also carry a USB (and a Murideo 6G , can't afford the 7th and 8th yet ) consist of excerpts of movies that I have collected over the years .
I normally bring them everywhere with me to run things on TV screens I see and fortunately most TV merchant and my friends seem to be tolerant with me so far  . 
Unsurprisingly the TVs I owned are mostly from LG and Sony . I am still looking to get a 2000 series but the 2000 last year was a botched job .

Panasonic OLED has impeccable PQ but at the end of the day , that OS is just terrible .

Eg , one of the previous OS updates is removing the support of PLEX  , not a big deal if you have a BOX which you should by now .
But if you are don't , you are basically screwed .