Lame
This is just Space Invaders crossed with Galaga only without any of the difficulty or fun. Is it even possible to lose at this game? When you get hit you don't even die, your blaster just goes down a level... I'm shaking in my boots. I'd have been more likely to buy this game if I never played this demo, though I'd be more angry when I found out what I'd bought. In a nutshell here's what this game needs:
1. Better/more varied music
2. More backgrounds or just a flat space backdrop
3. Higher difficulty, as in you get shot you die
4. Secondary weapons that you might actually use or none at all
5. A reason to play this instead of the actual Galaga.