Why Must Read 10 Actual, Official LSAT PrepTests Volume VI: (PrepTests 72–81)?

The book is exactly what I expected it to be so it gets 5 stars. However, if you are using Kahn Academy, the free study program recommended by LSAC, this book is useless because Kahn Academy practice draws from it randomly in both practice and practice tests. I bought this book because I was seeing so many repeat questions on KA and I wanted some paper practice for my July test since it could be either digital or paper, but because KA draws from these preptests randomly, each test in the book gives me both some questions that I have seen and others I have not...which kind of defeats the purpose of gauging where I'm at. If you are using KA, this book is a waste of money.