Last year I had a 10" Memphis Power Reference dual 4 ohm sub with the Memphis ported enclosure (i.e. fartbox) powered by a measly 150 watts RMS in my 2007 Accord. Believe it or not, for an add-on the the existing factory 160 watt "premium" (yeah right) system, it gave me some pretty decent low end!
If I had to rate it, I would say the Memphis 15-PR10D4 produced deeper bass than the two 10" JL10w3v2 subs that are each in a .75 cubic foot sealed chamber powered by 500 watts RMS in my Civic right now. OTOH, the two JL Audio subs w/500 watts are loud as fawk when compared to the single ported PR10D4 @ 150 watts.
Then again, my JL Audio 10w3v2 subs were a bargain boner sub too because I picked them up for $90!