This book seems to elicit mixed responses from Dark Tower fans. Some of my friends love it, others hate it. And I can understand both sides...

The wraparound story, that of Blaine and the return to the path, almost seems forced and orthogonal to the meat of the book.

The inner story, that of Mejis and Susan Delgado, is ultimately good, but at first I was very put off by it. It felt like it took a long time to get going. I even took a many month break (at roughly 20% complete, iirc) where I had mentally checked out of the book. I picked it up again on a lark over Christmas and plowed thru towards the end. As I did I found myself more and more engaged with the story.

I get why this story exists, and I think it's well done. But I also understand why it frustrates some King/Dark Tower loyalists. I look forward to moving on to the next book, though I might take some time before I dive right in.