This insider's guide was published after the 6th book in the series - Lover Unbound (V's story) and contains a short novella I read and reviewed separately - "Father Mine".
Took me long enough to get to this Insider's guide, I had it even before I started re-reading the series I just didn't find the right time to get into it. Thing is, if you read the books a long time ago then some of the things you've forgotten so I'm quite happy I decided to wait to read it after a re-read of the series.
This Insider's guide have a lot of fun and games, interviews of the Warden (As she is often called) with the brother, a summary of what she has to say about the writing of each book, her experience as a writer, funny quotes from the books, few deleted scenes and "slices of life" (Which are small entries she posted in message boards relating to day-to-day with the brothers).
It's was really great reading all that. I actually spend the whole day reading it and right now I kinda feel I have a BDB overload hehe
The reason I'm giving this one 4 stars though is you have to be a HUGE fan to love it. If you're into the books just read the novella separately. I love the BDB world and the brothers, I do, but I think that if you're not obsessive with the series you won't enjoy it as much. For me it was more a book about the Warden than a book about the brothers. I skipped some parts I didn't find that interesting, a lot of the background to the interviews (I'm not into reading the setting of an imaginary interview between author and their characters), and I did skip some things containing Phury and Cormia (I'm not interested in their story or their characters).
It was interesting to read the way the Warden writes and how she envisions the brothers in her head and writes what she sees and don't describe her writing as something that she does but something she records. But at the same time, after reading most of it I feel like I'm more into the finished work itself and less about how we got there. So I enjoyed reading this one but didn't fall of my feet. I think I would have preferred more about the brothers themselves, history or things we didn't know and staff like that and less about the writing itself but that's me, I'm sure there are a lot of people who were really into the how and the unique interviews that gives the realistic feel to the brothers.
My recommendation - if you're a huge fan - don't you dare miss it out! But if you're into the books and not obsessed with them just don't miss "Father Mine".