Footprint Peru Handbook is original in its kind as it focuses on information and not storytelling.
It has more up-to-date info on the things you actually need in day-to-day travel, most of it presented in a factual way rather than using endless pages of interesting but not-really-necessary info.
From a tour operator point of view, I need to know as many facts as possible in order to prepare, quote and carry out the tours we offer to our public. The Handbook is a great source of information in this area, as I don't have to read around the stories, but get the facts presented in a direct way. Due to the inclusion of much better maps and a very serious work at updating the info accurately, the latest edition is a big improvement, and one of best single guides on Peru currently available.
If you decide to visit the awesome Manu Reserve in the Amazon Jungle, fly over the mysterious Nazca lines, or If you hike the Inca Trail on your way to Machu Picchu, this guide is a must as you'll find all the data you need.
As a matter of fact, if you decide you're going tojust Cusco, I'd advice to get this guide instead of a Cusco-only one. You'll find all you need in Footprint Peru Handbook for sure.