I think the industry needs to step up and start giving us reference transfers for every release. This is what separates blu-ray from uhd and from downloads. The quality jump just isn't big enough. Not like it was for DVD and Blu-ray. We deserve better transfers.
Sent an email for Oppo support today explaining how the player locks up when playing mad max on UHD Blu-ray. They responded and said that they're on it.