Allow me to start off by saying I am by no means an audiophile, and don't feel it necessary to spend more on a sound system than the components I am connecting to it. This subwoofer nicely complements a small bookshelf audio system, and if you intend to use it as a secondary audio system, or in an apartment or other setting where you can't have it up too loud, it sounds very nice at lower volumes.
However, that's about all this subwoofer is good for. It is obvious that the driver and amplifier are of good quality - they can handle low frequencies at room shaking volumes with ease. Unfortunately, the box is poorly constructed, resulting in "port noise" that completely overpowers the volume of the bass it's producing at frequencies as high as 50hz. Considering the box is allegedly "tuned" for frequencies as low as 35hz, that is unacceptable. (For reference - while frequencies of 20-35hz are largely inaudible, they are the frequencies you "feel" during explosions etc in movies)