You got the mechanics down well. Once I figured out what all the bars and meters did, it was really fun switching around between the cannons and blasting away! I liked the challenge of getting in the rhythm of the pattern of the gun switch order and the switch cool down. Once you start to feel it, the game flows well. 

Good simple game :) my high score is 71 :D

Good game. It feels natural to play and the enemies come at a good pace

Very fun game! The only thing I didn't find very intuitive is when you switch between weapons, Since there are three of them, I have trouble remembering what weapon is next. But overall, it feels like a very solid entry. Simple but well executed :)