It's not that this is a bad game. It actually looks like a really solid game, but only under the correct circumstances.
This game seems like it would be great if I were playing on a New 3DS and had four friends in the room with me. Or even having four friends I could coordinate with online. But, I'm here by myself with a 3DS XL.
It seems like this game was built from the ground up with four player co-op in mind and playing single player just feels lacking. The fact that I'm not playing on a "new" 3DS means I don't have that analog nub that functions as a second analog stick. So, instead of traditional dual analog stick FPS controls it's a huge step back.
Again, this game isn't bad, it's just not for me. If you do happen to have four friends to sit down with and you all own "new" 3DSes I bet you would have an amazing time with this game.