So far I have found Authentic Beauty to be a very good book. It is one that really makes you look at your spiritual life; where you are at in your walk with Christ as well as seeing how you can improve it. Personally for me, I saw some areas that I had sinned in way back when and never really taken care of those things. I believe that is probably part of the reason that I felt like I haven't been growing spiritually like I could have been. I have asked God to bring to mind any other areas that I haven't taken care of and as he does that I pray forgiveness for them and repent of them. It is a really freeing experience. I know there are some things that I still need to take care of but I am ok with it. God is walking with me thru this process and it is definitely worth the time and effort it takes.
It has been a growing experience for me so far and I am hoping that the more I read the book, that God will continue showing me things that I need to do. You might end up hearing more about this book as I read it. If you ever have a chance to read this book...do. It doesn't matter if you are older or younger I think it could help women of all ages :)
Here are some more links from The Christian Pundit about modesty: