On a TV Screen you can see a difference between 720p & 1080p. On a Computer Monitor or a Hand Held Device there is no difference except 1080p uses a lot more Bandwidth than 720p which will take extra buffering. Once they get that HTML5 Player implemented across all Platforms sometime in 2019 that should help speed the playing up which will be less lagging. Once HTML5 is implemented that's the end of Adobe Flash Player which can be troublesome as well when watching streams.