or
1 x HSU ULS-15
or
2 x Elemental Designs A7S-450's
or
1 x Seaton Submersive
or
1 x (Pair) Elemental Designs P7-650
or
2 x Dragons

That is the problem with people who finally get a very good sub. They crank it because they can't hear it. Like David says, it should not call attention to itself.
A pure sound quality sub will sound like an acoustic bass when listening to music. You should be able to close your eyes and imagine the bass player in the room with you. The sound is effortless. The subs that you have listed can all do that if properly set up. They are all large enough to provide the bone crushing output needed to watch action and sci-fi movies as well.
And you will not hear the sub rattle. These enclosures are built like tanks. You can browse the eD forum and see pictures of them building their enclosures on the CNC machine. Epik at one time posted internal pictures of their enclosures. The opposing drivers of the Submersive keep enclosure vibration at a minimum. SVS also make quality components. That is the least of your worries. At reference levels you will have windows, doors and maybe walls that will be vibrating and making noise.
Finally, I'm a fan of the Behringer Feedback Destroyer as a parametric EQ. I used it to flatten the response of my dual 15" DIY sub. It took about an hour to measure the in-room response, graph it and make the appropriate changes on the EQ. Besides the EQ, the only other equipment I bought for this was the Radio Shack analog SPL meter. That is something every home theater enthusiast should own anyway.
-Robert
Finally, the Dragons.. are only powered by 600rms. So i am not feeling strong about them either.
I might be totally wrong on my assumptions, please correct me wherever i am wrong.
Thank you
