I love this series! It is smartly written and doesn't talk down to the intended YA audience. I often avoid YA because it has a tendency to focus too much on emotional drama than an actual plot. Not the case here! The fact that this really cool YA world is intertwined with the adult series has added awesome bonus points to Sherrilyn Kenyon for creativity.
My only semi-complaint/observation is that the setting feels very current even though it is supposedly set in the late 90's. I understand that the audience has to be able to relate and for many reasons (outside of the plot) it is necessary not to distract the reader by overly framing the time period. And to be honest, it's not like it was so long ago that things are wildly different, and anyway most high school experiences are the same regardless of time. So, I don't fault the author for leaving out cultural time identifiers or adding a little more emphasis on technology than may actually have been realistic.
Still, it's really great book that would be enjoyable at any age.