I love my Focal subs, I wouldnt trade them for anything. I wish I would have purchased the 130V2's before I left, and I will eventually, just cant right now (too many motorcycle riding miles to go).
My buddy built all the enclosures that customers requested, so him building my box was only natural. Its kind of a bandpass, the woofers face backwards but the sound comes though a port that is the same size opening as my ski hole. My specifications for the box were "give me as much trunk room as I can get and I dont want my trunk to rattle at all" and "make it loud" and "use these speakers". The 11"ers are plenty loud for me, but after 15 years listening to bass systems, I really dont want it bass-heavy, just a good sound. Pop a bass-heavy cd in there, though, and it will rattle the mirrors pretty good. The 13"ers are just going to play louder given the same power and all other things equal, you'll like them I'm sure.
The front of the box matches the slope of the rear seat. The back (trunk side) is flat and my amps are hidden next to the shock towers kinda up high. When you pop my trunk all you see is a carpeted wall that is about 12" forward from where the factory one is.
-There are 10 kinds of people. Those who understand binary, and those who do not.
-If we ever forget that we are One Nation Under God, then we will be a nation gone under...Ronald Reagan