That's why I use sheetrock screws. Now, if I could just get the suspended ceiling to stop vibrating. The SMS-1 is on my short list of pieces to acquire. I think it shouldn't matter if you use one SMS-1 for multiple subs. I would actually think this would even be better. If you equalize individual subs, what assurance do you have they will act properly when the signals are blended? Of course, I only care about a single listening position as I built my HT room for myself. Other people in the room are still blown away anyhow and probably don't notice as much as I do when things are slightly out of whack.