I'm not a union guy. Mainly because I'd heard several of the "myths" presented in this book growing up, and because unions that I've been compelled to join throughout my life have been particularly ineffectual.
But this book is really good. It successfully tears down a lot of the untruths that are out there, and additionally points out that some of the beliefs about unions (such as corruption) do exist on some level (and that is intolerable.)
This book would be recommendable for you (or someone you know) especially if they/you are politically conservative but also open-minded and receptive to other viewpoints.