I've used more editors on my new book, Only In Key West, than I did on The Gay Detective.
I found that there is a difference. Using one gave me a clear direction and less stress, whereas, using three pointed out more
specifics and gave me migraines.
I should point out each of the recent editors had important points and helped me develop deeper characterizations.
I also learned that using a proofreader for the final version, who had no knowledge of the book was critical. Her fresh eyes pointed out POV problems and incorrect assumptions that we had all missed. I strongly recommend this.
Nathan Bransford has some suggestions on editors. Check out his March 22, 2017 post, blog.Nathanbransford.com How to know if you have a good editor.
Whether you use an editor or not be sure to have beta readers or another writer who can be objective and is not afraid of being completely honest with you.