The only reason that I would give Hourou Musuko a 5 rating, is because I love the Manga way to much. I might have had too high of expectations for the anime, but if I have a main grievance, it is the fact that they started the anime 20-30 chapters into the manga, and tried to make up for the loss of character development and plot, by having flash backs. I felt that with such limited time, (12 episodes) they weren't able to do such a beautiful manga justice. At all.
Tl;DR-I was severely disappointed with the anime, but I love the manga.