Pros:
    1. 4K at 144 Hz even though it is 4:2:2 10-bit is simply amazing for games. I don't run this refresh at the desktop since the reduced chroma is more apparent.
    2. 4K at 120 Hz 4:4:4 8-bit on the desktop makes it the best desktop monitor I've ever used. Super clear fine text, snappy mouse, low input lag precise mouse movements. Hardly anyone has a 10-bit workflow on their computer so 8-bit + FRC is not a hindrance.
    3. Stand is nice and modern, looks good and does what it needs to do.
    4. Games in HDR at 144 Hz 4:2:2 10-bit look just fine. No real reason to use 98 Hz 4:4:4 10-bit HDR unless your FPS won't exceed 98 FPS anyway (very likely).
    5. Colors are excellent. Quantum Dot film really has made this LCD standout. Ensure SDR Colors sRGB is set to "off".
    6. FALD is pretty quick to react to movement. Keep on "Gaming" setting.
    7. Wide gamma range and black boost for those that like to have the advantage in a game.
    8. Motion clarity is slightly better at 144 Hz over 120 Hz. Pixel transition speed may not be quite as fast as the 165 Hz 1440p IPS gaming monitors, but it is fairly good.
    9. On-screen aim reticles for those that like hardcore modes.
    10. HDR+G-Sync+144 Hz+4K is an amazing combination and experience.
    11. DC dimming.
    12. FALD in SDR. Even though the monitor allows you to turn it off; don't. The combination of IPS and direct FALD without local dimming control leads to extreme BLB and IPS glow.
    13. Contrast ratio greatly improved by the FALD.
 
    Neutral:
    1. 4K at 27", very good clarity. It is a neutral point for me and not a pro since I would have preferred 32".
    2. AR film. It is much better than what they put on TN panels these days, but still short of my preferred semi-gloss.
    3. Build quality. Not the best or worst I've seen. Joystick control on the back feels a bit flimsy.
    4. Mediocre 4K Blu-Ray playback via the HDMI 2.0 input.
    5. Light sensor on top of monitor. Auto brightness is not adjustable if turned on. A bit too dim for my liking when enabled.
 
    Cons:
    1. Fan. I normally wouldn't care too much about the fan but it is audible. And it is always on. It even stays on for a few minutes after you turn the monitor off/standby. They really want to make sure this thing stays cool. To be determined if it is for the G-Sync chip, the FALD backlight, or both. Could effect monitor longevity if you plan to keep the display outside the warranty period. Although a fan would be easy to replace.
    2. Wish there was some sort of indicator (LED color change?) to indicate when HDR was active.
    3. Not a con for the monitor per say, but you will need some significant hardware to push this display. My OC'd Titan V struggles to keep up (90+ FPS) in a lot of newer titles with higher graphics settings at 4K. 4K is still very punishing and may continue to be so even when the next GPU generation comes out.
    4. Auto black level in OSD doesn't appear to do anything.
    5. Haloing is there. Not very noticeable in bright games but you will notice it in dark games such as horror/space shooters, menus etc. It is IPS+FALD, that's just the way it is.
    6. Some GPU's won't show boot-up screens on the monitor using the DP.
    7. If you use a aftermarket monitor arm, you may have to cut breather holes in the plate for the fan to breath.
    8. 300 nit maximum SDR brightness. Perplexing to me considering how robust the backlight is. Most monitors these days have 350 nit minimum and gaming monitors pushing over 400 for those of us that like to play during the day in brighter rooms.
    9. Even though it would be extremely hard to run at 4K, no ULMB. I feel this has been a wasted opportunity of the FALD backlight.
 
    Overall for desktop use and bright games/first person shooters like PUBG and the Battlefield series, there is nothing that can hold a candle to the X27. Including a 2018 OLED. The amazing clarity, colors, high variable refresh rate plus HDR makes it a real treat. There are some significant drawbacks, most notably blooming and the fan, but if you want the best gaming monitor on the market, look no further.
 
    8.5/10.