From last time the OLED went on sale (same year model, but 55" instead of the 65" this time around):
Commentary on OLED burn-in/image retention, motion handling, input lag, semi-comparable models for the price, and an overall endorsement.
Response to questions about OLED viewing angle, HDR performance, game modes, and latency in processing.
TL:DR - Conclusion
LG is the undisputed king of OLED, and as many technologies (like QLED, other quantum dots, or whatnot) try to match it, nothing other than plasma has, or will produce a similarly brilliant result. The motion is inherently faster, less blurry, and will show you the weakness of certain types of film sources. The screen brightness is less than LCD, but nothing to be concerned about, unless you want it in a super-brightly lit room - like full daylight plus reflective lights everywhere. But it performs well in bright rooms, and with muting reflections. And it OUTPERFORMS the black levels, contrast, and thus most HDR experiences on other screens. It is fast enough for all but the most competitive of PC gaming, which would require a gaming monitor to get any significantly better input lag times. For most people who watch movies, shows, and have more than just one news channel on all the time, burn-in is not the overwhelming monster that some suggest - I have installed, calibrated, and continue to service over two dozen of these, and only one person was abusive enough to cause any retention/burn-in.
This is a beautiful set, with great features, and a decently capable smartTV system, if you care to use it. Not the best smarts, but certainly the best picture. Picture quality on the newer 2018 sets has changed very little for even discerning viewers and enthusiasts. As always, refurbished is sometimes a risk, but this is a decent price on a potentially AMAZING television.