What is the real difference between 4K streaming and ultra Blu-ray discs? Scott Wilkinson says that most of the Ultra Blu-ray discs on the market are now 4K HDR. Streaming content is making the move to HDR, and several of the TV shows streaming are in 4K. Netflix is the leader in this. Stranger Things is going to be streaming in 4K HDR as well, but it won't be as good because of bitrate. It'll top out at about 25 Mbps streaming, and it's data compressed, while 4K Blu-ray HDR is about 100 Mbps uncompressed. Renting Blu-rays is an option, but finding HDR Blu-rays can be a challenge. There's RedBox. But at the end of the day, for now, you'll be buying the 4K HDR Blu-rays you want.