I agree with you that if you really have to subwoof the SC Vs (and I don't really think you should unless you're willing to put up with the garbage that's down there as well as the rest and have a strong back to move the damned things around), the only way to go is stereo subwoofers, as the Dunlavys and the Duntechs are among the few speakers which actually seem to be able to localize low bass sources (don't ask me how, I never could figure that). A single subwoofer may run counter to that, unless you can cut it off steeply (24 db/octave or higher) at 20 hz or so. If you have unlimited funds and a big enough room, the Dunlavy towers are probably the way to go. But there really isn't that much down there in the regions you're going for that you don't already have a dedcent taste of at 22 hz.