I had a custom menu, a mixture of WP and other pages (on the same site), so can't as I do on other sites have all pages added automatically.
But adding pages (new will be nearly all WP) a pain - both remembering, and dragging through an increasingly long list.
But without having to change a thing in my existing menu, this works perfectly, adding new pages to the parent I set.
On another site I've been wrestling an auto menu a must (some quite non-teccie people will be adding pages) but I wanted a group of pages under one heading but without that sub-level for short urls. Now I can easily do it.
Only snag, which was already there but it doesn't remove, if someone forgets to set a parent then the page will be added as main heading on the menu, and v slight inconvenience, anyone going back into change will have to make the page draft before setting the parent.
A 5* plugin as far as I'm concerned.