The LG 27GR83Q-B has good accuracy before calibration in the sRGB mode. It isn't perfect, though, as there are inaccuracies in the white balance and colors, and even gamma is off. Luckily, the color temperature is good, as it's only slightly on the cold side, but not enough to be noticeable. Unfortunately, the 'sRGB' Game Mode locks many settings, including Response Time, so if you want to use any of those settings, you'd have to use another picture mode that has more oversaturated colors, as you can see here.