I have read it twice, and I think that it is a great book.
It is obviously a semi-official SSPX biography, so, obviously, some inconvenient ideas and quotes are left out, but, as a biography, it is a great work.
My favorite part is from his youth until right before the council. It shows how great Abp. Lefebvre was as a "regular" churchman, and not as a reactionary.
His life before the council is little know, and I think that it is the best that this book has to offer. We all know what he did from the 60s on, but most people know only that he was a missionary in Africa before that.
He was a truly great missionary, and had a significant contribution to Senegalian politics and society in general.