OLED graduation has been discussed to death on AV forums, its not as simple as the panel itself. Early panels had issues where poorly compressed material would create quantisation errors and blocky noise in dark areas but a movie with no compression artifacts looks perfect in dark areas. Later panels dealt with this with what we assumed to be better dithering algorithms but most issues on OLED are caused by poor source material, push great in, get great out, push crap in ..... I dont notice any banding at all on my OLED, even at near black, unless its on the source and mine is gen one. There were some differences in the panels, the later 2015 models tended to be better and a few lucky people like me got a really good example, although I had to send two back with terrible near black vertical banding which is the real Achilles heal of OLED. It can still be a bit of a panel lottery but its a lot better than it was, i'd still buy my current OLED over any LCD, FALD or otherwise as i'm a dark room viewer and OLED cant be beaten in this field, once you go OLED there is no going back unfortunately
