The answer to this question rests with the author. I would posit the following question to the author: What do you hope to accomplish from this approach? When I receive a query letter from an author who quotes positive statements from an editor my immediate thought is that the quote is taken out of context. In many cases I already know that the editor's statement is part of a rejection letter. An author quotes an editor stating that the work is "...a masterpiece." This is true but the full sentence reads, "This work is hardly a masterpiece."
As an agent, editorial quotes give me clues as to where the manuscript has been and subsequently rejected. While some may disagree with this advice, I suggest that editorial quotes be avoided altogether, as they do not enhance the author's chances of an offer of representation.