Will a 600 watt Rockford Fosgate 15" T1 sub hit harder than 2 300 watt RE Audio SR 12" subs?

Which setup should I go with. And which ever setup I choose, I will have a Polk 600 watt RMS amp and a 1 fared cap powering the sub(s). By the way, the sub(s) will be in a ported box.