If you are looking for maximum output and max room pressurization, then a big giant woofer in the corner will do that best. If you are going for max quality with music then a pair of subwoofers placed semi-near the speakers will be better. If the subs are open baffle, it is even better for music (this is my approach in my 2 systems).
If I were forced to use box subs again, I'd do 2 smaller subs near the main speakers, and then over time I'd buy 2 more subs and place them randomly throughout the room to create a nice swarm approach. The swarm approach gets the smoothest, most even bass loading in a room with box subs.