I've chosen three book reviews that are both professional as well as broad in scope. The first is from the New York Times book review. It was written by Raye Snover 6/15/2003. You can access the review by logging on to the NY Times website listed below. The second is from Road Trip America, and the last one is from Civil War Book Review. In my opinion this one is the most informative because the author, Eric Campbell is actually a park ranger at Gettysburg. After I finished reading this review it was evident that Mr. Campbell's knowledge base regarding Gettysburg gave him a greater insight into McPherson's walk through Gettysburg.
Hope this is helpful. The websites are listed below.