Good luck with that! For sound quality subs, I would take the Dayton HO 10s over either of those.
Then again, if you want to have it super loud in the 40 to 80 Hz range, the DD subs are your speakers! Just don't expect to feel anything in the 20 Hz range and prepare to be disappointed if you listen to anything other than metal or rap.
Also since you are mentioning weight, those DD1510s are going to require 1.5 cubic feet NET per sub with a lot of port area. You will probably be real close to 5 cubic feet gross by the time port and subwoofer displacement is taken into consideration.
You do understand that you are taking advice from a forum full of individuals in their almighty quest to hit 150 decibels on a termlab, don't you? While there are better sounding subwoofers than JL Audio w6v2 and w7 series, you really don't save that much money! I hate to say it, but you pay for quality, especially if you want something to play perfectly flat in the 20 to 80 Hz range while taking your vehicle's transfer function into consideration.
OTOH, if you are only interested in being LOUD from 35 to 80 Hz, without regards for a flat frequency response, there are better and cheaper alternatives than JL Audio to achieve these goals.
Since you are concerned about weight, have you considered a pair of 15" subwoofers mounted IB such as the
AE IB 15 or a pair of
Fi IB 12s? Then again, I don't know the details of your vehicle, so this may not be feasible.
