The performance of the pb13 and f212 is pretty well documented, so they would make a good point of reference, but I think you should bring in some more obscure and newer subs, like many already mentioned in this thread. And really, there are more powerful subs commercially available, so you should do more to put the "ultimate" in the ultimate subwoofer shootout. There are subs from Danley, Seaton, ED, and Funkywaves which would walk all over those subs, and I'm guessing they would be more eager to participate than JL Audio or Paradigm.