If you're a budding scholar in Pre-Raphaelitism, I would avoid this book. If you've already done some research on the life of Elizabeth Siddal, this book is an interesting read. This book doesn't follow the traditional layout of a biography, starting with birth and ending with death, but acts as a historiography: a study of what has been written about the subject. Jan Marsh looks at several biographies about Lizzie, considers the sources, the scholarly intent, and the history at the time, and considers if the biography is reliable or not. For instance, Violet Hunt's popular book on Lizzie is full of inconsistancies and has been tainted by the author's own image of who Lizzie really was.
In short, this book is worth buying, only if you have another good book on Lizzie. I recommend The Pre-Raphaelite Sisterhood, also by Jan Marsh, which is a valuable reference source.