If I could, I would give it a 3.5 or 7/10.
Most people who started the manga did so because of the anime.
The anime has done an amazing job to the point where I would say it is superior to the manga. It has additional scenes which are even better in the anime with more detail. For example, a fight you see in the manga might be 1 or 2 pages, but in the anime there are more "frames" "panels" showing better the abilities of each character and the strength of the opponents, you really feel the battles.
The anime does not lack anything in terms of information, it shows everything, even the most insignificant details that the manga has.

Now, why did I mention all this? The reason is simple, very often when people want to read a manga it might be because there is a lack of information and scenes that the anime didn't have or even a complete change of the story, a very common phenomenon in anime for cost and production time cutting.
Here, the exact opposite happens, the anime adds even more.
Another reason is for artistic perspective, many times because it's an anime the studio might not have capable enough illustrators but that is not the case with this anime.

So then, what is the reason to get the manga? For me, the only reason I saw is to support the artist/mangaka and to find out what happens earlier, since the anime is quite far behind, the series stopped at volume 8 at the moment (2026).

I won't sit and talk about the story, you can see it first in animation. The only thing I will say is that the manga is slow and doesn't have a particularly interesting plot to grab your attention to get the next one, I think the story really gets interesting from vol 6 onwards and gradually peaks at vol 13 and 14 which are the last ones written in English so far in physical form. This doesn't mean it won't get better but for now I consider it "mid".

It's not at the level of Tokyo Ghoul or Death Note by any means. I put it in the same category as Claymore, quite good but if you are someone who has just recently started getting interested in manga there are far better options.

Also, I should mention that Viz is an incompetent company, very slow to release the manga and doesn't make nice covers, if you see the German or French ones you will be surprised and the fact that they have the book ready within 2-3 months after the Japanese release while the English one comes out after almost a year.