As for the characters, there are a lot of varieties. Each character somewhat portrays his/her country. Each one is unique that attracts a lot of fans (I'm one!). Though there are girls, the show presents guy-to-guy pairing. Because of this, it became a good material source for shounen-ai/yaoi fans.
The sound effects are good but for music, there is only one ending song entitled "Marukaite Chikyuu". But eventhough there is only one, different versions of it was released soon after. The original is sang by Namikawa Daisuke, Italy's seiyuu. Then, the version of Germany and Japan came after it. Now, America's, England's, France's, China's and Russia's version is available too (others version should come out soon). There are Character CDs as well. The lyrics change at some point but it’s pretty much the same.
The art is simple but great in a way. But of course, if you're looking for a high-definition or something, this isn't the best choice.
My overall grade for this Anime would be an 8 out of 10. I really enjoy watching it especially when the episodes get really comical.
