I was surprised to find this book, a niche publication to be sure, at my local Borders outlet. I'm into track history in general and pre-WWII in particular, so I picked it up.
Cunningham is a fascinating character. He was burned nearly to death in a fire when he was seven years old, and it took him months before he could walk and years before making a full recovery. He was scarred for life and it had a major effect on his racing. After his competitive years were over he ran a BoysTown-like ranch which took in young people in need of help.
The book is a bit disappointing, I must say. The author appears to have done little if any research besides interviewing Cunningham and his family and friends, and reading newspaper clippings. Cunningham is described in universally glowing terms, and while he surely was a remarkable man, everyone has some dark side to them. Also, the author appears to have a frustrating lack of knowledge about track history (he includes several factual errors which were easy to check) and track in general (such as saying outdoor mile races have 16 turns). And unlike the fantastic book about one of Cunningham's track racing contemporaries, Seabiscuit, we learn essentially nothing about his training regimen.
It's worth reading, but it's only worth a trip to the library. Don't go out and cough up 15 clams for it.