The way I see it, subwoofers are not emotionally based appliances and when someone posts that they want recommendations for a thirty foot long, open room, I'm giving them a recommendation that will suits the room's acoustics and a room that large needs three, even four subwoofers. Below is what the OP posted in their original post:
"Room size: Rectangular, open ended room. The ceiling is 8 feet. The wall that the TV
and three front speakers is on is 17 feet wide. The room is approximately
30 feet long, but it opens up into the kitchen and basically the rest of the
downstairs, so it is not an enclosed space."
The room is 4,000 cu ft and an open design. Despite what the poster posted about his bass preferences, two subs in a 4,000 cu ft, open venue is not even come close to doing this room justice and pretty much, everybody here posting, knows this. In my opinion, two subs is going cause this room nothing but sonic fits.