I found this game to just be okay. I thought it was a bit too simple. There could have been better design. I still liked how I could destroy my enemies. It didn't seem like anything that special. The music was fairly good.
It was certainly easy to understand. It just didn't seem like anything too noteworthy. I think you need to work on the details. The health bars on the enemies were a nice touch. I assume one torpedo would be enough to sink one of these things.