I have an ASUS ROG Swift OLED PG27UCDM, a 27-inch 4K OLED.

I’ve owned it for 13 months now and it’s been nothing but positive. To be clear about my use case: I don’t watch movies on it, I don’t game much (maybe 10 hours a month), and most of the time it’s just a browser or a few terminals on screen. For terminal work, this monitor is a blessing. In a fully dark room, only the text glows, nothing else, and it’s genuinely enjoyable to look at. I haven’t noticed any issues with text rendering either: at 27 inches, text is crisp from 50–70 cm away, and the pixel density is more than adequate. I suspect the 30+ inch OLEDs are where text clarity starts to become a problem.