GOALS are very important! One of the car audio shops that I go to sells JL and RE audio products... He rated subs in this order XXX, w7, MX. The XXX dominated the lows, the w7 played a wider band width(with authority), and the mx.... I wouldn't like it.... If you're doing your own install, get jl over re! JL can take customer abuse more than the re can. I know cuz i went through a xxx in a couple of months where my jl w7 are still going strong from 2003 Some ppl will say that jl charges too much if you mess it up which is true, but RE charged me $250 for the XXX and it took 4 months to get it back!!! Way tooooo long!!!! So goals would be SQ, Spl, or a mixture of both.... If you take some time, you should be able to find something on every sub this site has to offer!!!! Between a XXX and an XCON, I'd be more willing to bet on the XCON:-) Also, its all in the install. direction sub is facing, sealed/ported, tuning freq, etc... to many factors.... Have fun researching!!!! I learn something new everyday!!!!!