So zom100 has an anime too which is still ongoing. And if I compare the anime with this, anime is better. So firstly, the casting is good. They did a good job in finding the cast but the dialogue delivery was a bit weak. So japanese movies and dramas r known for their story more than their acting skills. Acting is still a weak point for japanese entertainment which is getting better slowly. So this movie too had those bad acting moments.
Talking about the story, so as I said the anime is going on too so that is more true to the manga. But the movie is somewhat a vague representation of manga. The movie is not completely based off the manga but only some specific scenes have been taken and patched together. Well I m not saying the movie should have been an exact copy of the manga but I m just pointing out the details.
Next the CG is hilarious ? I mean if u have seen some CG japanese movie or live actions u would know how badly it is done. So I would not talk about the CG.

So coming to conclusion, I would say u can watch it but it's just a pass time. U shouldn't be expecting something out of the world story before watching this. Re-watch value is 2, just bcuz I'm being generous.

Overall, a disappointing movie with good cast but bad direction.