I thought this was a good game. My biggest complaint about it is that it's basically a tutorial. It's just the same thing over and over. I can understand how you would have to know this stuff. I guess I should have figured out how to change guns. It was mostly the same thing over and over. I still enjoyed that.
It was interesting to see what kind of technique you could come up with to destroy the orbs. I really liked how the falling debris exploded. Granted, that hurt you, but I never died from it. I can imagine that happening to some enemies though. Of course, they would be the enemies in that case.