Loved it! If you fly down (or probably off in either direction) you can fly off the map ;) It's a really fun game, though I think that maybe you could decrease the turning speed as you grow so that you can't do insane manoeuvres when you are as big as the island! Also it gets to a stage when you are SO big that you can barely see the smaller planes at all! With the last boss, you could make it so that you can damage the turrets first before destroying it - would be a fun way to take him out!