I liked a lot of things about The Core - although the first half of the book was too, um, confrontational for me. However, I would never do CC because it gives up too much time and control for me. I homeschool so I have that control and I would hate to leave home one day a week, every week, and not do the things I want to do.
I also hated the way Bortins kept saying "Classical Educators do this or that." I've been reading Classical Ed books, websites, and other publications (starting with WTM) for 9+ years now, and I can tell you, there is nothing that all Classical Educators do. I wrote a book review on my blog in 2010 when I read it.