This is very much like a student film with a decent budget -- for a student film. So if you judge it on that basis, it's ok. If you judge it by other horror films you'll see in a theater, it's dismal.
First, the acting, driven by the director's creative choices, feels forced and inappropriately "dramatic." People are peeved for no reason, angry without cause, emotional without motivation, shake their heads in disbelief and/or disapproval far more than real people would, and just generally behaving inappropriately for the situation. In other words, its actors are directed like they were in a hotel porno. This is done partially to justify their subsequent victimization at the hands of a serial killer, since this is not a teen movie, hence the filmmakers can't use sexual promiscuity as the setup for the murders.
This thriller also lacks an essential item for serial murder flicks -- tautness. The pacing isn't tight, isn't compact. It's sloppy and diversionary, and because of that, it struggles to hold our interest, partly because it keeps releasing its hold on our attention, and partly because we stop caring about the characters nor their welfare, and we even stop believing there's a phantom lurking about this opera.
Maybe this director/writer is using these films to build his resume of "watch how many trick camera shots I can do to prove I deserve more investors for the horror projects I wish I could make?"