Believer? It will warm your heart and strengthen your faith. Skeptic? Give it a go, see if you rethink your ideas or see a scam. Lost a loved one? You may get some peace. Have young kids? You'll know that if it's as written, it could not have been made up.
A lot of times you have to make a conscious choice to believe. I think this book easily fits into this category. I had moments of tears and am making that choice to believe it. Even if you're unsure, you can read it in about 2 hours and not lose too much time with it. Give it a shot!