I bought three of the less expensive ones, two 9.2s and a 6.5. I agreed with the grade on 6.5. The other grades were probably a bit soft, but not too bad because I stayed away from the books that looked too softly graded. Some of them were graded ridiculously softly (9.6s that looked like 8.0s, etc.).
I see the soft grading as adding volatility. Some people buy the book, and some people buy the label, so whether these softly-graded books sell for a strong price or a weak price at auction will depend on who shows up to bid on that particular book.