(major spoilers) This is why we can't have original films
This was a good film. Maybe not go to the theaters good but DVD or Netflix good.
Look at every other Jason Statham, Chris Pine, Christian Bale, Matthew Mcconaughey, cop/crime drama. You have a romance at the beginning, you introduce the good guys then then bad guys. Bad guys go kill the bad guys with a big shoot-out and then they have kiss at the end.
The Factory didn't have any of that, just a solid crime mystery. There wasn't really any romance thrown in. The cops really haven't figured out what is going on yet, there is only really some circumstantial evidence tied to the real killer. And even after that, the cops are still turned onto the wrong guy.
tl;dr: I liked the darkness of the killer. I liked Cusack as the opposed detective and I liked the plot-twist at the end.