There's the root of a decent game, which is what makes its failings all the more apparent.
Project Root is an overhead shoot-em-up in the vein of Desert Strike. Truth be told, Project Root is not terrible; it looks fine and it plays fine, it just does nothing particularly well. The best thing about the game is the fact that it is kind of open-world, which is uncommon for the genre. The game's biggest drawback is that it is dull, the environments are about as stereotypical as it gets, the jet is very basic, and there is no real story. None worth caring about that is.
If you have a real hankering for a top-down shoot-em-up game, then this will probably scratch that itch, but unless that itch is turning into a rash, I don't recommend Project Root.