RU8000 is non QLED series, which lose out to X9000F which have Sony triluminos display (another word for quantum dot display) which in Samsung Marketing term called "QLED".
RU8000 is Edgelit, X9000F is more expensive with FALD and of course OLED is the current flagship on TV lineup for current technology, microLED is too expensive so don't talk about that.
First, the display whether is IPS, VA or OLED panel, whether fixed 60Hz or can the panel support 120Hz higher refresh rate. Does the panel include quantum dot technology.
Then dimming technology used, if compare LCD LED, whether is cheaper Edgelit or the more expensive FALD. OLED is class of its own.
RU8000 cannot even compare to those 2 you mentioned. Is like comparing a Mercedes C180 vs CLA180, how to compare? Haha!
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