I am contemplating purchasing a TCL 75S425 75" TV. I currently happen to own a 70" Vizio "smart TV." I have found that while the Vizio allowed me to install my most popular app, Plex, its interface paled in comparison to that of the Roku Ultra. One particular thing I really like about using the Roku Ultra is that I can DirectStream 4K HDR HEVC titles from Plex without any issue, but they will NOT play directly with the Vizio. I'm not sure if that is why I lack the trust of a player built into a TV, but I was curious as to the "horsepower" of the built-in Roku player of the TCL 4K TV with that of a stand-alone Roku Ultra.