I have Carplay on my Tahoe. It's very cool to be driving down the road, say "Hey Siri, get me directions to 1010 Main Street" and instantly have the Apple navigation put that up on the car's screen. It works very smoothly.
I also switched from Spotify to Apple Music, which has much better Carplay integration. I can navigate pretty much all of the Apple Music menus right there on the car screen, and can also say "Hey Siri, play album Dark Side of the Moon by Pink Floyd", or pretty much any other album I can think of - or any of my playlists, and it will just happen.
The text integration Carplay is slick as well. On the whole it really is just like using your phone, only with the car's screen as the interface rather than the phone itself. Now that I have it I would miss it if I did not.
The Tahoe has a touch screen. I do wonder if Carplay would work as well with an iDrive knob.