Good...
I'll give you credit for the scripting part of this game but I'm not diggin the music, graphics, or the controls. Could definately be improved. Music goes without explaining.
However, the graphics can be summed up pretty easily... raster? Who does raster in flash for a game like this? I mean maybe you're just going for that specific look or something but... it's just not that great. But man I can relate... cuz I absolutely suck at graphics... I mean I could do good if I spent hours on it but I'm lazy.
Then the controls. Man I have no idea how you'd fix that. But the controls right now are confusing as hell, I dont know where I'm going. Instead of making it so taht the left and right controls the angle at which you move, make it so that if you push left you move left, right moves right, up moves up, etc. Then aim/shoot with mouse.