I took my 5th edition books and compared them to the new set they have on the shelves. They are identical, other than some larger fonts and different color text. Same goes for the 1001 editions and even to the verbal 101 book. I actually found the 5th edition set in a public library and scanned them at home, printed them at work. No money spent and I have digital copies of them now. Look around for the older ones, nothing has changed in them, the company is trying to fix minor mistakes (ie for multiple choice answers, sometimes the choices are A B B D) and they want more money, of course.