Get the animated GIF, this game isn't worth your money!
The intro was the most enjoyable part, to me. And the intro is extremely hilarious. As for the actual gameplay, control and engine were solid, and it has an attainable skill level. It certainly has an arcade-type feel for it.
The actual gameplay was really not all that memorable. I don't remember the Music, or sound Effects at all, and it doesn't seem to offer anything (with the exception of the intro) that you couldn't get in another 2D shooter.
The Bottom Line
Average. The only reason I would purchase this game is to watch the introduction. And, even then, it's not that hard to find a movie dumped from an emulator or and animated .GIF, or maybe even a .mpeg or .avi file with the intro. Honestly, the intro is what made the game famous. (or, infamous, heh, heh)