Storyline: Here are some bad guys. Shoot them down because explosions are pretty. Graphics: Beautifully stylistic with a retro-arcade feel. Music: Catchy and fun to listen to. Gameplay: addictive, and somehow managed to make money grinding is fun. Could use a fullscreen mode, but going by it's current strengths, 5/5.
@ Naverino: It's not so bad. You get premium content currency by doing missions and as part of the Gift-per-Day, rather than just by shelling out IRL money.