I have about 6000 cubed plus openings to a hallway and a stairwell to fill with glorious bass. Currently, the original Dual SVS CS Ultra package, serial numbers 16 and 17 is providing all the bottom. The Ultras are on the back wall split on either side of the seating area. I've tried them in various locations "stacked" and apart but the current setup with BFD yields the best results most likely because I got tired of moving them all over the place. Talk of the Epik 18" Conquest "pressurizing a room with bass" and the sheer prowess of the 435lb ED dual 18" 97-900 have peaked my interest. Can't really beat these offerings with a walking tall stick for $2000 or less delivered. I remember plunking down a few hundred more for the Ultras. I really like the one box solution to big bass in big areas and I have the room to easily accommodate both offerings. So what is my problem? There is absolutely nothing wrong with Ultras. "I" have the problem. They do a fine a job but they will most likely be available to someone at a good price along with a Samson amp very soon.