I don’t know which of them is better, but amazon.com shows me several translations or adaptations of Cabeza de Vaca’s telling of his adventures, you may want to check them out.
Genghis Khan and the Making of the Modern World. I could not put this book down. It’s incredible the innovations this guy implemented.
I read this one. There is another book about it called The Loss of the Ship Essex, which was the account written by a couple of the survivors.