This is just an Opening Movie for the upcoming game Digimon Survive.
Characters seem to be interesting, with a variety of personalities that you would commonly find in a Slice of Life and School themed animes, but the plot has its nice touch of mystery, making Digimon (as a franchise, maybe?) seem a bit darker in terms of story, for this game, is supposed to be about the hardships of being lost in another world, having to "Survive" and make choices that may imply a high cost.
There is not much about the plot in this ONA, actually.... but I am going to rate
the story based on what's known about the game so far. So 10, for now ;)
It was very well made, and the song that was in it is kinda melancholic and touching.
It's not necessarily going to be a Masterpiece, but I am definitely expecting something good! Bandai/NamcoBandai have always taken risks when it comes to making Digimon games, experimienting so that they can find ways to improve them.
As for my enjoyment,.... I love digimon, so I mostly enjoy this kind of stuff to the fullest, even if too much wasn't revelead on the ONA yet (given that I also know more about the game due to other info available on the net) :P
Hopefully, maybe they will make an OVA or an anime about this game.... or not; but one can dream, who knows :P