The game is very good!
The use of theme is but questionable to me, but it does fit.
I gues my compaint is that the gameplay isnt that interesting idea-vise. You just fly backwards and shoot at whatever. But the way it feels is.. just awesome. The speed, the sound, the look. All feels just amazing.
Also it wasnt clear even after reading the decription what is going on. On the second try I easily beat it. And it was very fun :)
Good stuff