[psicodude]

First, ignore that chart posted by Corsi because it's stupid. To suggest that there is little to no difference between 480p and 4K is silly. Try watching the next Flames game in 480p and let us know how that works for you. I will admit, however, that the jump from 1080p to 4k is not as noticeable and you would assume. I think this has more to do with the video sources being compressed/messed with because of bandwidth limitations. A true 4K stream is going to want around 30mpbs, which is problematic for a large percentage of this country. The debate is becoming moot, however, as 1080p screens are becoming extinct.

What Aleks post was about is a change in how inputs and outputs are managed in 2017. The "old way" (3 years ago) was to have use your receiver as the brain of the operations. Like you posted originally, you have a bunch of devices plugged into the receiver and one cable going from the receiver to your TV. You either manually change the input or use a smart remote to match whatever device you would like to watch, and the receiver outputs that content. You can still go with this model, but you would need a new receiver that has both 4K hdmi inputs and outputs as the receiver is "passing through" the video portion of whatever you are watching to the TV. Your other option, which Aleks properly explained, is to make the TV the brain of the operation. You would plug your source devices into the TV and then run one hdmi cable to your receiver. The technology called CEC/ARC merely sends a signal from the TV to your receiver to turn it on or off. You may want to look at this way of doing things if you aren't interested in buying a new receiver because your new 4K TV comes with the 4K hdmi ports already. You don't have to worry about which resolution the source is pushing out because the TV is able to automatically switch between 1080p and 4K.

I also have a Vizio TV and the casting works perfectly. The TV needs to be connected to your home network (wifi or cabled) and your mobile devices will be able to communicate with it. When inside an app like Netflix, YouTube, Spotify, etc. just press the "Cast" button and select your TV. It's generally that simple. The downside of casting is that you don't have a menu or anything on the TV. So instead of scrolling though movies on netflix that everyone in the room can see, you are looking at your phone/iPad and telling it to cast to your TV. Same result, just a different experience. It should be noted that casting is not supported by all apps or devices, which was explained above.

I hope that helps a bit.