I've tried basically every service, and I think Xcloud and Stadia represent a 'generational' improvement in streaming experience. Maybe the problem is that PS Now is tied to PS3 and PS4 hardware poorly optimized before low latency streaming, but I don't find streaming on PS Now to be playable. With Stadia at least on Destiny, I'm happy with the perception of input response. I've played enough of that game on PS4, and I don't have any palpable adjustment to muscle memory playing on Stadia. Xcloud is less impressive because it's fixed at 720p and my phone screen, but I also felt good playing Halo Infinite. When I miss a headshot, it's from my own lack of reflex rather than the tech failing me. When I play Uncharted 4, or worse a PS3 game like MGS4 on PS Now, I feel like the tech is not up to the task for more than previewing or briefly revisiting a game.
Stadia really deserves a shoutout on the video quality front also. Even on the Chrome browser which is not the pristine 4k stream, it still looks a hell of a lot better than any other streaming service. I've played Ghost Recon Wildlands on Geforce Now, and not only was it constantly disconnecting, but macroblocking was very noticeable. If your connection is stable, Stadia's 1080p stream is a step up from every other cloud option to date. I just played an hour of Destiny 2 on my family's 25Mb/s wifi connection and had 0 visual hitches the whole time. On 4k it's close to perfect. Looking at the chromecast version on my 4k tv, it's hard to tell the difference from a direct hdmi output. No other streaming I've tried is close to Stadia, including local streaming options like Steam Link.
