First I'm a Physicist, so I have a built in bias.  I have the hardbound Lecture series, but bought this to read in bed, travelling, or just out in the yard.  I have lent this to other non-physics types so I'll take their word that this makes these subjects easier to understand (not easy to understand).  Like any Feynman book, it will take a read or two to fully understand what he is getting at.  This book just makes it easier to reread each section as needed.