Overall Rating 7.3 out of 10 - For the most part a really good show, not very consistent with quality.
I recommend watching.
This is rare and unusual show. In some ways its prototype of K-On! that I reviewed a while ago. Parallels between Mio and Rio as well as Sawa-chan and Felicia are really glaring. Sad that they did not add Noel to K-On!
However, if K-On! is well polished show with lethal doses of moe, then Sora no Woto is more of rough-cut version. That means that some episodes are hit, and others miss. However, it also means that here you can see a lot of never before (or after) tried things.
The better episodes include the one about Fiesta de Lumieres for example. In general town in which the story is set is full of various legends and mysteries, including the one about Maidens of the Fort. Episodes dedicated to festivals or legends look spectacular and have an unparallel fairytale mystery feel to it. After watching more than 250 anime titles, I have never met show that is as good at fairy tale mystery as this one.
Episodes about more mundane stuff however are average at best. They are not bad, but hardly worth it on their own. I tended to skip every other episode when I rewatched it, however it probably worth watching even them at least once. Because of them I somewhat lowered the average score of this show, it could easily reach 8.0 without few of nastier episodes.
Both introduction and conclusion are solid. Intro focuses on Kanata and her introduction to 1121th Platoon of Helvetian Army. Conclusion mostly focuses on Noel and her guilt for creating weapon of mass destruction. Last few episodes are very solid, and I will not spoil any more of the plot.
Technically this show is about military, but most of it is about daily life of a platoon and routine duties of military in peacetime. 1121th platoon man one walking tank (that does not work), looks after border fort, they are quartered in, and trumpet time once a day for the town next to a fort. That latter part is the reason why locals call it singing fort.
Art direction is good. While it does look noticeably more dated than K-On! however, things they depict are very imaginative and pleasant to watch. Once again festival episodes are the ones that let art direction shines best.
Music is great, it has few tracks, but what it has is unlike anything else. I can recommend OST on its own.
Occasionally show even gets philosophical and tries to elaborate about existentialism and other such themes.
I definitely recommend this show, especially for those who saw many other shows and want to try something different.