Meh.
I understand why people like it. I understand why people don't like it. Myself, I didn't like it.
First of all, this had nothing to do with the madness plot at all. Maybe you didn't want it to be, but in that case, don't call it madness or let it refer to the series, because that is downright insulting. The only thing that was relatable, is the shooting of the faceless henchmen with a cloaked red-glasses-wearing guy.
Secondly, as a game itself it had nothing special or challenging at all. It was just shooting. Heck, what cool is it when I can't even die and have unlimited ammo?
Now I don't want to be too criticizing, there were some good things as well. I liked the artwork, some of the points of view were very well done (I refer to the scenario with the ladder).
And as Mr. Gripped mentioned, the idea of a "how many times do you get hit" gives at least some entertainment and challenge.
Conclusion?
Meh.