For those who have /will read the book, the show is never nearly as good as the book, but it is not bad either.
In a way it can make you even sadder than the book, or at least the music in it does, so beware because it is a hard topic.
The acting was kind of great, but Miwa`s character was too annoying, more than it should have been imo. The portraying of Tomo and Kyoko was alright.
If we`re talking about staying truthful to the novel, the show made some changes which I didn`t particularly like, but it did not affect the overall end either.
Overall, if you like mentally disturbing themed shows, this is for you, but if you don`t like these topics, I wouldn`t say don`t watch it, because it can give you a new experience.