That speaker is worth every single penny and I'd buy it if I needed it and had the money.
While obviously NOT a 33" speaker, the Focal 15" beast he used is perhaps one of the finest woofers produced for hi-fi applications.
Unfortunately, that speaker is NOT a subwoofer, it is a woofer designed for amazing performance in the 30Hz to 800Hz range. I am sure it operates as low as 20Hz, but I doubt it has significant output below 25Hz, or so. Two of those used as bass bins in a three way setup similar to mine would be unbelievable!!!
I love the cabinetry, as well. My next speakers might look something like that.