I love when books do that to me. Super satisfying and easily one of the best recommendations for a book around. "I couldn't put it down" has to be the height of complements for an author.
Reminds me of something I read from Roger Ebert when it came to film criticism. He was about to go see "Who Framed Roger Rabbit?" for the first time for the paper and bumped into some fellow critics. He asked if they were gonna see it, too. and they responded, "Oh, we reviewed it already. We're gonna go see it AGAIN!" That was plenty of endorsement right there (and of course, Roger wrote a helluva good review on it, including this meetup in the notes).