I am upgrading the subwoofer portion of my theater and want to go with dual subs after reading the article here about teh benefits. My budget is $3000. I have been looking heavily into the DD-10 and the Optimum-12. I can save about $600 going with the Optimum over the DD-10, but I don't want to lose a significant amount of performance for a little savings. My constraints are subs that are 70lbs or less shipped, I live in Okinawa, Japan and am limited to USPS priority shipping. Other than that, there really are no constraints. I am not married so the WAF is N/A. My listening space is approximately 1800 cubic feet, but I will be moving into a larger space (unknown exact dimensions yet). I equally listen to music, movies and play games. I also looked into the Sunfire HRS-12's which seem a bit lower compared to the 2 velodyne models. I owned an SVS SB-12 Plus and wanted to add a second, unfortunately I couldn't find anywhere to purchase a second online as the product has been discontinued, so I decided to upgrade to a higher quality subwoofer. I would love any other suggestions you all have that would fit my budget and desire to go dual sub. Thanks for the help!