I agree that a banana/cigar refer to the same general shape. And see lots of variations, curious as to which variant you attach "Bean" too. I just glanced at 4 or 5 Bean rifles by 4 Beans and see two variations on
their "banana boxes".
Yes, "cigar" is a better descriptor, but "cigar box" sounds like something else entirely, so I say "banana box" to refer to the long slim boxes of sheet iron.