Mtx's Head to Head Competition

I was recently browsing mtx's website and came upon this..http://www.mtx.com/Flash2/volume_displacement.cfmThey claim this will decide which speaker will play the loudest by multiplying the sub's sd by its XmaX. This just seems fishy to me that their MTX 7500 12 will outplay a Memphis MOJO 12 and the Kicker L7 12. There are other odd outcomes according to this calculation. I was just wondering if anyone had some input on their methods of loudness.

Sd times Xmax gives Vd, or "peak diaphragm displacement volume."  Higher displacement usually indicates better low-frequency transducer.  As far as being "louder," this is only one of many factors that will determine SPL output in a subwoofer system.  Highest Vd does not always equal highest SPL. Support the12volt.com

Also keep in mind that companies measure Sd and Xmax differently from one another. 

One word... HYPE.

Another word...propaganda