12" xs-xxx or 12" JL W7?

I've been researching on trying to figure out which sub would be the best bang for my buck. Im debating on a w7 or xxx. I want the boat to pound but still have the sq. Ive got a 12" ported box already built to go under the helm with a 12" Rockford Fosgate P3 in it. I have it in my truck breaking it in and it beats pretty good but not like my 2 JL W6's i have. I have a free air 10" Rockford Fosgate under the helm and its pretty much pointless because its so far up under the dash and its not loud at all. Im ready to get a good sub in there that ill be happy with so any advice on the best sub for this project would be great. Thanks in advance.