If I'm totally honest, it's as good an image as the B7 OLED but brighter.
We watched John Wick 3 on 4k Blu-ray on Friday evening. After setting up the TCL TV on Saturday, I watched parts of it again and to my eyes it was just as good.
I should image there are edge case scenarios where, side by side the OLED would have the upper hand.
But with my eyeballs, under most of my uses cases, I don't think I have any regrets going from OLED to mini LED.
I learned over the time I've had the OLED that when it comes to 4k Blu-ray, it's the source master and how it was shot in the first place has more influence on how good an image you get.
Outside of the image quality, there are a few minor niggles with the TCL TV that am working through at the minute.
It didn't play nice with my AVR to start with. Had to disconnect every and reconnect in priority order to get CEC/HDCP 2.2 handshakes to work.
The only issues now is that the native Netflix app isn't working with Dolby Vision for some reason, yet Disney+ is working fine.
And even though I have power CEC control turned off, the TV turned my amp on when I turned on the TV. But I've had this issue with my LG TV too, so I know it's the flakey nature of CEC.
Edit:
So for whatever reason the Dolby Vision and Netflix seems to be limited to Drive to Survive, as other content works fine. Also had the same issue on my Nvidia Shield. So who knows what's going on there.
CEC issue are doing my head in. Even with power control turned off on every connected device and the TV itself. The TV still turns on the amp when I turn on the TV. The only way to stop it is turn off CEC control. But if I do that then I don't get sound from my amp when I actually turn it on and select the TV as then source.