I currently have an amplifier that is 600watts (max) connected to 2 10" Subwoofers (PowerBass Brand with a sealed box) and I have recently gained ownership of 2 12" Pioneer Subwoofers already in their own ported enclosure. I was curious, would it be better to keep the PowerBass subwoofers I have in my car already, or should I use the new Pioneer ones?

Here are links to all of the equipment:
Amplifier: http://www.powerbassusa.com/asa-3002x-2-ch-amplifier
PowerBass Subs: http://www.powerbassusa.com/s-104x-s-104dx-10-subwoofer
Pioneer Subs: http://www.parts-express.com/pe/showdetl.cfm?Partnumber=290-125

Just to recap the powerbass box is sealed and the pioneer box is ported. If that makes a big difference.

Any feed back would be appreciated however, if any of you have work experience in the car audio field I will consider your advice more thoroughly.