Nearly Excellent.
Although not the most original idea, like Necrophades said, that can't really be helped with this genre. And that wasn't even the problem. What I like most in these games are the power ups. And the power-ups in this game were terrible. Most of the time they either did nothing to help you (with the exception of the shield powerup), or actually hinder you as in the case of the sweeping main laser. And the boss battles were actually easier than the rest of the level before it. That being said, I thought the graphics were astounding, especially for this type of game. So, for me, I would prefer better power-ups, and maybe make the ship a little faster. Still, a fairly good game.