I found Sparrow Hill Road at the bookstore when I was picking out books for my birthday present from my parents. I've read and loved several of Seanan McGuire's other books, and I definitely don't regret one of her books being a birthday buy. :D
For those familiar with the InCryptid books (Discount Armageddon, Midnight Blue-Light Special, etc.), Rose's story takes place in the same universe, and while some of the characters from that story are mentioned very rarely (the Healy family), I have only read Discount Armageddon so far and didn't feel that I was necessarily missing anything. :) I do think that someone who is more familiar with the universe will definitely appreciate the mentions, though!
Going into Sparrow Hill Road, it is necessary to mention that it was originally serialized. Due to the original format, there is a lot of repetition across the stories, so if that's something that you as a reader wouldn't be able to look past and would get horribly annoyed by, Sparrow Hill Road may not be for you. That said, there is a really awesome story here, so it would be a shame. :)
The collection opens up with "The Dead Girl in the Diner," and the story completely blew me away and even made me cry. It was creepy, sad, and awesome all at once. While some of the following stories didn't grab me quite as much as that one did, they all showed us another piece of Rose's world, and I really liked what I was seeing. I will warn potential readers that the stories don't seem to have a connection between them until about halfway through. At that point, the skips through time between stories becomes much smaller and each story is more closely linked to the one before it.
While I liked the short story-esque aspect of the collection, it also has the downfall that, for the most part, once a story concludes, the reader doesn't feel a huge need to continue on to the next one until they want to know what Rose is going to get herself into next time. I think this is basically just because of the original way the story was told, so be prepared for the beginnings of most of the stories to slow down a bit, but I will say that once each story gets going, it's hard to put down again.
My only complaint in terms of the writing (which I'm not factoring into my rating) is that a lot of the terms of this world are mentioned and then not really explained. While it can be gleaned from the text what and who these terms refer to, I personally found it a bit overwhelming at first. I was happy to discover that there is a field guide at the back of the book which explains some of them in more depth (however, there are some minor spoilers in the explanations, as a warning). My confusion with the terms may be related to not having read other stories from this universe, though, and the field guide at the back of the book cleared up the grand majority of my questions. I also admit that it would probably be a little strange for Rose to need to explain them, since they are and always have been a part of her world. :)
I LOVED the idea of the different layers of America, and the ghostroads, and the twilight and midnight and daylight and all of it. I just... I can barely express how much I loved it. Such an awesome idea and McGuire does awesome things with it. I was completely entranced by the imagery of the several layers of America, and I just... AHHH, I just loved it. So awesome. Overall, I found this to be a really enjoyable collection, and I'm really looking forward to (hopefully) seeing where Rose's story goes next!