There's an update on Audioholics about this shootout, and some insanity surrounding it.

http://www.audioholics.com/news/editorials/subwoofer-shootout

In the attached discussion it has been surmised that it was Axiom who was opposed to the groundplane measurements, and pulled advertising from the site.

Pioneer PDP-5020FD, Marantz SR6011
Axiom M5HP, VP160HP, QS8
Sony PS4, surround backs
-Chris