Who "rates" these records? We need to know so we can figure out what is overrated and underrated.
If I would try to make my own criteria, I can say that the most underrated U2 "song" (but it really isn't), is the "Theme From Mission Impossible" by Mullen and Clayton. It went all the way to 11th on the Billboard charts - not bad for an instrumental featuring the non-singing members of U2.
Yet, that song has never been played live or included in Best Of U2 releases - even though a non-U2 song like Miss Sarajevo made such compilation.