As with other JIVE fan book series works, quality is very high, at least externally. No, I haven't read it yet. And I'm not going to read it yet because, despite the fact that I have some ideas about the ending (other than nice boat), I've only watched half of the series so far. I'm not going to ruin it for myself.
I will update this after I finish watching the anime (late Feb to early March 2008) and actually reading it. For now, enjoy the beautiful cover illustration.