Has anyone used "Quiet Rock" sheet rock in room?

Has anyone used "Quiet Rock" sheet rock on the walls and/or ceiling in their listening room? I am building a new dedicated sound room and I am trying to do all the "small stuff" (i.e. clean power and a well built/designed/acoustically treated room). All input would be appreciated.
Unclejeff--that's interesting and we will actually explore some possibilities of using that in combination with a layer of sheetrock and green glue in between. Same material layers (5/8 sheetrock) with green glue in between give really incredible results for $ spent. I think we may do some experimentation with this Densarmor board. Is it similar to blue or green board?
It can replace normal sheetrock or greenboard. My contractors are using is throughout the job. It has a paperless backing so it is not receptive to mold. There is some fiberglass involved, I think.

Again, my own 'test' is one of a field observation, nothing else.
Field observations are sometimes where discoveries are first made. We regularly learn things from builders and then incorporate them into our plans so that everyone benefits.