Warning! May contain spoilers, or anger MI-fans.
The three first books of the series are OK, I suppose. They're fairly rounded and nice for long rainy afternoons. (Or, if you listen to the audios, as I did, to help you ease the boredom of ironing, washing dishes or other household chores.).
IMHO the author should have stopped there.
But she obviously decided to make fanfic of her own creation, which was, I'm sorry to say, quite detrimental to the whole story.
The fourth volume already wasn't what I would have expected. Too much teenage angst that got only worse in the fifth. The lengthy and overly frequent descriptions of "golden skin and hair" of "glistening abs" and "darkening amber eyes" and of long, hot kisses were slightly wince-inducing. Even worse were the repeated detailed descriptions of garments of all kinds, that seemed to stem from a bad fashion catalogue. The battle scenes were also frequent and quite boring and seemed to fill up the pages non-stop.
All that heavy teenage angst was simply too much and seemed to occur in a regular loop. (I guess I'm not much into that kind of drama, it just annoys me, lol.)
But what annoyed me most was the barely veiled "reference" to the Potter series. Too many characters just reminded me of JKR's creation.
Luke, the friendly caring werewolf just screamed Lupin.
Father/Son Valentine/Sebastian reminded too much of Lucius and Draco Malfoy, even the platinum blond hair was there.
Redhead Clary seemed a "better" Ginny Weasley and her mother Jocelyn a living Lily Potter.
Other elements made me think of various other fantasy books or of Wikipedia sites about mythologies.
Should you be in search of good, interesting fantasy, you'd probably be better off sticking to Neil Gaiman or Sarah Brennan. If you like lots of teenage love drama and descriptions of incredibly perfect teenage bodies and fashion, as well as battle scenes including daggers, swords and monsters of all kind, go for it.
Oh, and yes, there are lots of vampires, werewolves, angels and a few interspersed muggles, er, "mundanes" there, too!