I've had my new TV for about a month now, and I'm absolutely blown away by how gorgeous and immersive the home experience has become. Its HDR-capabilities are world-class, and the brightness makes Atmos titles shine (pun intended) like nothing else I've seen on streaming services. I'll be buying a dedicated 4K blu-ray player after new year's, to really make the most out of the TV, but it's already damn impressive. I've used an Xbox One S as a 4K player until now, but it lacks proper HDR and audio capability. A dedicated player will really make the most out the whole set.
I managed to snag a Harman Kardon Kardon Multibeam Citation 1100 this January, for about half price, along with the subwoofer (also 50% off); the combination is incredible. I have yet to watch anything above 25% of max volume, for fear of ruining my neighbor's day. Amazing experience!