Honestly with 4k remux you really feel the difference on a big screen, the detail and color depth are on another level compared to compressed stuff. The tricky part is that not every platform handles this format properly, some still mess with the bitrate or push their own compression on top. Worth taking time to look around before you settle on something. Guys who are serious about picture quality usually end up on dedicated sites rather than mainstream services. One option that seems to have the right idea about this format is http://vidity4k.com/ .