So here is my variant on the question. Due to WAF issues, I have to go with subs inside my built-in cabinet at the front of the room. (I previously owned a PB-12, which my wife hated.) Looking at my size constraints, I'm probably going to go with the SVS SB12-NSD when it comes out this summer. The sub will go in a cabinet in the corner of the room. Room is over 5000 cubic feet, has hard wood floors, and opens to kitchen, stairs, and hallway. I will use the sub primarily for Home Theater. Will listen some to music, but rarely above the moderate level, if even that high. I also found my old SVS had far more power than I actually used (which, of course, was fine with me). I've ordered SBS-01s for the speaker system.
I know that the SB12-NSD will be underpowered, and am toying with the idea of getting a second SB12-NSD and putting it in the cabinet next to the first sub. What do people think about that? Also, is there any advantage of getting the SVS AS-EQ-1, either for one SB12-NSD by itself or dual SB12-NSDs?