I rate it 4-1/2 stars because I really enjoyed reading it despite my issues with the ending. A great book! 
 Not your typical Stephen King book..... 
 Some readers have said the middle of the book was too slow, too long and boring. It was a little slower paced, but I found it all very interesting and necessary to the overall story. So sit back and take your time reading this one and enjoy the ride......... 
 I do have some mixed feelings about the ending. I felt like when it neared the end.... the pace sped up so much that it felt rushed ... like King was tired of writing and just threw an ending in there to get it over with. I enjoyed all the slower paced buildup and would like to have seen it flow into the ending a little more smoothly. 
 Contains spoilers below........... 
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 The romantic in me wanted Jake and Sadie to ride off into the sunset and live happily ever after. But there was no way for that ending to work... it had to end just the way it did with Jake going back and resetting the past to put history back on its true course. I thought the "last dance" scene when Jake goes to see Sadie in 2012 was a nice touch to the ending. 
 What bothered me the most about the end of the book was the changed world that Jake went back to after stopping the assassination? I thought it was very "Stephen King like". Of course I expected changes.... afterall, there would have to be consequences to changing the course of history.... but nothing that extreme. King could have written a very interesting alternate history instead of taking the easy way out with his sci-fi version. The possibilities are endless...... and would have been so much better than his dark extreme version. 
 If the ending had been a little better, I would have given it a full 5 star rating.