I sent my second CX back because of banding. First one was dead on arrival, but third panel has been flawless.
HBO max stuff is highly compressed down. Notice crap even on LCD panels on various colours. Bit different when you watch a 80gb blu ray to a 20gb streamed one. Mad Max and Blade Runner 2049 are good ones to test. Watch the uhd disk version then a uhd streaming version and you will see what I mean.
Not really worth buying an OLED for the majority of people as they don't watch UHD content in the main and are happy with highly compressed streaming services.
BTW, HBO max is only really good for watching that old sitcom "Step By Step", something that 99.9% people in the UK haven't even heard of as it was only ever shown briefly on itv in the mid-90s for a few weeks. Shame HBO max isn't available in the UK either.