Note: I hate quantifying a manga scoring in multiple categories - story/characters/pacing etc - because to me that's just min-max type of scrutiny that dilutes the holism of the entire work. So, I'm going to score the entire manga as a whole and nothing else and tell you why I liked the manga. This is, in my opinion, the arc that satisfies the most - IF you've been following all the build up so far (which I assume you have why would you otherwise be reading Arc 7 of a series directly?). First things first, The arc is LONG (compared to other Higurashi Arcs). It has 6volumes and each builds up upon the other from Page 1. There are no fillers, no club activity arc, no extended "I wanna take you home" scenes. Its purely business and starts hard from the start.
Keiichi, who has so far been energetic but kind of passive? (Even if he's been a main character so far) really acts like a main character this Arc.
The reason I am giving this a 10 (not so surprising for me when it comes to Higurashi) is because there were times I had tears in my eyes. I never have tears in my eyes. Never.
Anyway, Read it.