Do quality books stand out in Amazon from KDP Print?

It doesn’t matter if the book is created by KDP Print or not. If the book is amateurish and poorly constructed, it’s going to get bad reviews. If it’s a quality book, then people won’t even notice, it’ll just be the way that it is. Unless you smack people in the face with the “this book is self-published!” dogma, most people won’t even know (or care) if a book was printed by KDP Print or somewhere else.

Exceptions might be for specialty books (such as full color photo books – with which I don’t have any experience yet) that may or may not print as well, but for standard black & white trade paperbacks, people won’t know or care where it was printed as long as it is easy to read and doesn’t fall apart.