[Exim] Mail formats?

Does anyone know where I can find information, including pros/cons on
any/all of the following mailbox formats? Also, I have read in the exim
FAQ on how to use MMDF format boxes, and of course unix format is
pretty standard, but does anyone know about setting up exim to do any
of these others?

          + mbox
          + mbx
          + mh
          + mmdf
          + mtx
          + mx
          + news
          + phile
          + tenex
          + unix