iterate ordered versus unordered containers

I want to know which data-structures are more efficient for iterating through their elements between std::set, std::map and std::unordered_set, std::unordered_map.

I searched through SO and I found this question. The answers either propose to copy the elements in a std::vector or to use Boost.Container, which IMHO don't answer my question.

My purpose is to keep in a container a big number of unique elements, that most of the time I want to iterate through them. Insertions and extractions are more rare. I want to avoid std::vector in combination with std::unique.