Cooler Master Tempest GP27U 27" 4K Mini LED Gaming Monitor (Open Box)

First, the good. The monitor is bright. It will give you a true HDR experience only really surpassed by an OLED (which personally I'd never want to use as a monitor due to eventual burn in). The problems start when you start doing non-HDR content while in HDR mode. Which you wouldn't think would be a problem till you realize basically all your computer software is SDR. Not too many games, although more and more are, support it and most desktop software will only use SDR. SDR content is very washed out. Seems to be a saturation or gamma issue as you can mostly compensate by turning down the Black Adjustment setting, but that starts to dim the high end of the brightness scale fairly noticeably. If that was all, I could make due with enough calibration and other tweaking.However there are two problems I just can't ignore. First, half the time when setting my Refresh Rate to 160 Hz the monitor and my other two monitors just shut off and never recover. I have to hard restart my computer by holding the power button. Then like 50% it'll come back up at 60 Hz or at 160 Hz. And it'll just randomly boot in 60 Hz after having been set to 160 Hz. I also had one time where the Nvidia Control Panel could not detect Adaptive Sync Support. I didn't have these problems when just using 120 Hz or 144 Hz.The final nail in the coffin was the local dimming behavior on SDR content. It was almost like the local dimming logic inverted on SDR content. Watch and HDR video and it is near perfect, but just browsing the web and go on a site with Dark Mode and you see the issue right away. The easiest way to test is to show an image with like a 70% gray. If you mouse over the image you can see as a local dimming zone dims as the mouse passes through it. That's not how that works. The mouse is pure white, you should instead see a halo as the dimming zone is brighter than all the ones around it due to the mouse cursor. That is just unacceptable and the only way to "fix" it is disabling local dimming which ruins your blacks, which is kind of the point with HDR. Ultimately it is this last point that forced my hand to return the monitor.4/5 for Gaming, only loses the 5th start due to the issue with 160 Hz1/5 for Picture quality, would be 0 if I could, for the issues with SDR (for the desaturation and local dimming issue)5/5 for Brightness, because it really does get BRIGHTThe other