If you love over-the-top action, exploding heads and not much plot, than you will probably love it. Great fun in those regards.
But if you want a deep story of any kind, you won't find it here. The chapters - excluding the first two - are episodic, which means you only get one chapter to invest in the characters and plot. Even with the three characters who remain throughout the entire manga, little to nothing happens with them to create any character growth.
In short, it's a fun B-movie-esque manga with lots of action and guns. And sometimes that's all ya need.