It's alright
I like it. I love the way it's played and I usually enjoy these kind of games. The only thing I have an issue with it's the upgrades. I wish the game would pause and let me choose an upgrade, because I usually find myself fighting for my life when the upgrade choice comes up, but end up choosing an upgrade I don't want while I'm dodging the enemies. It gets annoying when I get the side weapon and I want to focus on the main weapon. =/