I have Pluto on the Roku. The Pluto interface just plain sucks, so I knocked it out of my list.
Sling tv gives you a tv guide or channel icons to use.
I do not like the tv guide as it is too slow so use the icons as the Roku remote makes it easy to scroll.
The Pluto tv only has the tv guide. There is no back and forth between 2 channels that are widely spaced apart. I think you can setup favorites at the Pluto website but have not tried yet.
Works great for me and I like it Pluto.