This book--actually a collection of journal articles--is targeted at those who are serious about learning and practicing primitive technology for creating tools and weapons. If I were in that category I might have given it five stars, but as a casual reader just wanting to know a little bit more about how early man used what was available to him I felt 4 stars was generous considering the editing is not the best and some of the articles are a bit tangential to the topic.
Those serious about practicing the techniques described might want to avoid the Kindle version as even when zoomed in some of the photos and diagrams were fuzzy and hard to decipher.
But if you want to learn how primitive man created fire, evolved from the thrusting spear to the atlatl and bow, the specific materials used, etc., then this is a worthwhile read.