I'm struggling to review this film as I didn't actually hate it, but it's littered with flaws.
My main complaint is that it never really settled on a tone. At times this film is dark as hell, with some properly gruesome and grotesque ideas and scenes.
At other times it strays into Evil Dead style comedy horror with some of its action scenes and sequences. This shift was quite jarring and had they picked one route and gone for it might have been more effective.
The acting was quite hit and miss, with no particularly solid performances to mention.
In terms of plot it actually had some interesting ideas, but took way too long to get stuck into the meat of the story.
The soundtrack is pretty great though I must say.
Overall a bit hit and miss. There's plenty for horror fans to enjoy and I did enjoy large parts of this film, but it felt a bit rough around the edges.