Glad I didn't turn it off
Though I nearly did a few times as the acting and directing was so bad.
It only starts getting interesting about half way through and the gory end kinda makes up for lost time but it's never really explained or justified why she should start killing her 'friends'.
What I really didn't understand is why the girl who never did anything got her head smashed instead of that annoying, jealous bitch who 'only' got stabbed and choked? Would have been more satisfying to see HER get destroyed...