Just wanted to Know if anyone owns a Velodyne series ll HGS sub? What are the real world differences between the series l & ll? I already own the series l 15' HGS and I am trying to decide if I should sell this sub to my friend (for $1200) and purchase the series ll ($2300) or just keep it and buy another series l at $1600. Either way I am looking to own 2 of these monsters. I just wanted to find out if anybody knows if the differences are worth the extra $$$.