The stopover can be combined with the open jaw rules for pretty flexible routing that can somewhat make up for the lack of one way redemptions in some cases. (uponarriving.com)
United Airlines also has extremely generous stopover and open - jaw rules for many possibilities to maximize miles. (themilesprofessor.com)
Lufthansa has very generous stopover and open - jaw rules on award tickets. (meinemeilen.com)