Better than the First.
This is better than the first game, by large. The same basic concept, but it's still a tad easy. It's too easy to block every shot with your sheild, and there is no need to buy the upgrade, because I find that the bounced bullets don't do much, if anything.
I find it equally annoying that many people are complaining about enemies firing as soon as they come onscreen. For readers, you simply press the space bar to activate the sheild. Simple enough for an idiot who doesn't click on 'help'.
Still, my main criticism is still, this is a little too easy. Make the sheild not block all damage, or make its amount of time staying up less, because the easy use and invincibility of the sheild makes the game extremely easy in monotonous parts.
I am pleased to know that you also used the 'One Man Army' soundtrack from the last game. Best music I've ever heard.