the anime is split into 4 different stories. i will write my impression from the 4 of them.
TLDR; watch stories 1 and 3, skip 2 and 4.
story 1: the coolest of them. has different styles of animation, colourful, the music is very fitting. feels rhythmic and funky. there is very little dialouge and most of the story is passed through the animation.
story 2: felt depressing and so slow. i really dislikes the animation styles which were either really bad 3d, or real life pictures put through filters to make them become cartoonish(which also looked pretty aweful). i couldnt care less about the story which sucked.
didnt notice the music too much. i suggest not watching this one.
story 3: story is quite nice, the themes are of friendship and fighting. the animation is nice and colourful, fights have a samurai champloo feeling and are nicely done with their unique animation style and slow motion. music is good.
the story is really funny in its ridiculousness.
story 4: iv'e seen 1.5 minute from it but it was enough(i want to remind you that 1.5 minute is like 1/3 of that story because theyre short..)
its just some girl singing her story. i didnt like the 3d animation and nothing interested me in that story so i skipped it.
the ratings i gave are pretty much for stories 1 and 3. if i included 2 and 4 the points would drop by an average of 3 or more. trust me and watch just stories 1 and 3.