This is a review for up to episode 29 of a 52 episode run. The series is long since finished but I am uncertain as to when it will all be fansubbed so I am going to go ahead and review what I have seen.
Animation: This anime reuses cells alot. In pretty much every episode. Everytime someone calls their summon monster it is a reused cell. The fight scenes, all the special moves are just reused cells. The fight scenes are pretty cheesy. The non fight scenes are all fluid and when they aren't using their special moves, the fights are fluid. You might like this if you are pokemon or digimon fan. I never watched either show.
Sound: Sound is good. I like the opening and ending songs and the battle music is good. The voice actors are pretty good.
Story: This is mostly aimed at kids, but it does have some elements that would appeal to an older person. There are alot of kiddy jokes that an older person probably won't find funny, but there are a few genuinely funny ones that would appeal to an older crowd. I was ready to quit watching but the story really starts to get interesting around episode twelve. You also grow attached to the characters. This is not the type of anime I would watch for the cool fight scenes because the fight scenes aren't that great, but the story is intriguing. At first it seems pretty straight forward. Heaven users are good, Earth users are bad. Heaven users fight Earth users, end of story. But at episodes twelve and onward it starts to flesh out the story and characters more and you find there is more to the story. You're not quite sure what is going on and I am watching because I want to see where this story is leading. It does hold your interest once it starts getting into the main story and quits with the monster of the week stuff, although it does still do that.
Character: There are a lot of characters. Most of the villains and the good guys are all well fleshed out and none are too cookie cutter. You grow genuinely attached to the characters. There are several secondary characters that are pretty much just cookie cutter and have not been fleshed out at all. The main character is kind of bland, but Kogenta the Tiger Shikagami is cool and interesting as is his nemesis, the Tiger Shikagami for the Earth clan. There is also one character whom you have pegged as the typical sidekick who turns out to have some hidden agenda. There are a few annoying characters. Typical of Anime, it is mostly the females. All the females in this anime are pretty much irritating and useless or pining after some guy with no identity of thier own. However, there are alot of interesting side characters that keep you watching.
Value: I am never sure what to put for this. This is an interesting series with some rewatch value because you get attached to the characters.
Enjoyment: The animation is not that great but the story is good. The fight scenes usually aren't too good because they keep reusing cells. When the shikagami's just fight hand to hand it is pretty cool, but mostly it is them doing their super moves and once you've seen it once, it's not too interesting. The story is good and I am enjoying the series.