Spent the last several days , testing my C8 . This bad boy is kicking some serious asses .
I must say I particularly love the new BFI on C8 ,  I can sit closer to the TV without getting dazzled by all the hardcore action scenes now .
Also for gamers , the new dynamic tone mapping makes a Day and night difference for gaming  . Wouldn't recommend it for movies though  , especially those mastered in Dolby vision are already very bright .
Last year they patched the OLED with a nerf on the brightness and APL , causing the a lot of games , such as Horizon Zero to look way too dark. You can offset this by turning on dynamic  contrast, however this cause a lot of details to be lost behind the brighter area.  The dynamic tone mapping is different , they analyze metadata and selectively brighten zone or object carefully with the new a9 CPU , the result is HDR highlight and zones that look a lot more iluminating than any OLED TV, yet retaining most of the fine and delicate details on screen .
I know a lot of reviewers say it isn't worth the upgrade from last year , but that is because they are not primarily gamers . For me , this feature alone is good enough of a reason to upgrade from last year's model.
My verdict : if you are a gamer , the C8 along with other 8 series  ( except B8  ) are probably the most amazing TV money can buy now  . The AF8 seem to still struggle with input lag , and Sony's OLED approach to the HDR just doesn't seem right to me , they choose to go for the brighter route and overblown the HDR details ,  one of purposes of getting a good HDR display was to check out all the glorious details behind the bright and colorful lights to begin with .