Pretty fun for a few minutes.
The difficulty curve could be a bit better maybe? On easy it would it starts out with basically nothing on screen then becomes difficult very quickly. I little more time to build up would have been nicer I think.
Also power ups changing could be kind of sudden - died once or twice after the invincible power ended.
The backgrounds were nice though, and also liked the main menu music - would have been nice to have something playing during the game.