Here is my review of both books in print & PDF's too. This review is my first ever and it's coming from someone who's been playing D&D weekly since 1980, of why I purchased these books and why I bought the types I did, in hope that you see the value of them like I have. I purchased the Books & PDF bundle of these amazingly detailed encyclopedias, and I'm extremely glad I did the bundle.   I chose the books and PDF bundle so I can have access to the hard copies when at home. These hard copies together weigh almost 8 lbs and are completely packed with detailed and updated information without any filler fluff that you get in so many source books these days. These books don't have lots of wasted space, of various sized pictures on every page like too many store bought source books. In place of those pictures is what we all want and need, we get more useful and informative text to help DM's create fantasies for our players. These books even contain various npc characters, monsters and locations from numerous novels; Some of which, hadn't been in any of the previous source books. And these books do something I've rarely seen in other source books ( other than little footnotes here and there ) by being very inclusive with the multiverse of various adaptations of people, places, things and events throughout others takes from the original material; Mind you, these books are huge ~book one is 396 pages. ~ book two is 372 pages. These books are incredibly detailed with a plethora of information that starts back at the beginning, when Tracy and Laura Hickman made this world in 1982. Having the PDF copies allows me to have digital copies that I have on my laptop and on my cellphone, so I can read, examine and research, whatever I need on the fly. So as a DM, you probably do like I have and ideas pop into your head while you're not with your printed books to be able to research something and by the time you're at home with your books, you may have forgotten all about that question; This then becomes another integral mobile tool for DM's. Another bonus to the PDF's on your electronic devices is being able to enter keywords in the PDF search bar and then being able to scan those results quickly and efficiently to get to what you wanted while on the move. I hope my honest opinion helps anyone to decide what to do when possibly purchasing these awesome books.