I'm not rating it now cos I still have to read the sequence and I hope my opinion improves. In few words... 
 - the storyline is interesting, but nothing we haven't seen before. Quite like a female Percy Jackson with much less humour and much more girslish drama 
 - the narrative is quite repetitive sometimes, specially concerning a) Gwen's guilt over Paige Forrest/her Mum's death conection b) disbelieve in real mithological heroes (when she's living among them, no less!)