This is a surprisingly tight game, with a great art style. What's great is that it really is a demanding strategy game with a really well thought out mix of action and pre-battle preparation. Most of the mid to late missions are challenging enough that players will need to try a couple of times before victory, so just because of that there is a lot of replayability here. There is an impressive level of customization for individual characters, armoured units and skills. As the game goes along, more features and options are revealed, so that the game asks you to make decisions on a level not expected in the earlier stages. It's very satisfying. Mastering this game will take weeks. My only criticisms are that the cutscenes are quite long. Of course, you can skip them. Once you are in the missions, the pacing is perfect, and I really have no fault with the story. In that department it's a step above most games.
Overall, it's innovative, well designed, artistically quite nice and crucially, it's fun. Fans of strategy, war games and/or anime should give it a look.