Sharing “reviews” of my newsletter

It’s common practice to share book reviews or endorsements on our websites to promote our books, but I’m wondering if anyone has tried sharing subscriber “endorsements” of their newsletter on their signup pages. Some of my subscribers have told me how much they love my newsletters, that mine is their favorite of all the author newsletters they subscribe to, etc., and I know they would be happy to let me quote them if I ask. Has anyone tried this to help encourage signups? Thoughts or insights?