The headline here is that I almost never read a book in 3 days - but I did this one and I was up past my bedtime turning pages. 
 Stephen King has written this series across the whole span of his adult life & both the character and quality of the series change across the decades (and also between front and back cover). For me Dark Tower as a whole is often spectacular, sometimes a bit weak, but mostly very good. 
 The Wind Through The Keyhole (TWTTK) is set just after my favourite of the series 'Wizard and Glass' and focuses on the Gilead days (my favourite part of Wizard and Glass) so there was always going to be a good chance I'd like it. 
 This is a story within a story within a story, and most of the book is spent at the deepest layer of this Russian doll. King is returning to ground he last trod 15 years ago and it's as if he never left. 
 There's nothing in TWTTK that is particularly important to the Dark Tower story, no great insight into the ending of the grand tale or really into the characters - it is what it is, an exciting and imaginative tale told using characters (well really only Roland as the rest of his ka-tet feature only very briefly) that we know very well and want to see in action. 
 For me the pacing, atmosphere, and balance of mystery vs menace in this tale just hit perfectly and I got exactly what I wanted - hence the 5 stars up top. 
 Will everyone love this book? No - but I don't think many will hate it. 
 Can you read it cold, without having read the other 7. Yes, but you'd be missing out on a lot. If you read it before book 5 and after book 4 (as the #4.5 indicates) then that would be fine too. But certainly it's a must for all Dark Tower fans, and if you've not read King's masterwork ... then get to it! 
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