I've got a pair of the non-pro version, PC-2000. I'm not equipped to judge their quality other than frequency response (they follow my house curve to about 15hz), but I am happy with them. They're definitely way larger than I envisioned however.
They get more than loud enough to piss off not only my closest neighbors, but most of the building. I've never felt the need to dial up the volume past 12 'o clock, which was stupidly loud. I am not a hundred percent sure of my measurements, but I want to say that most of the distortion stems from resonances within my room rather than the subs themselves.
My only gripes are that the top... lid is a dust magnet, and that they do not feature XLR in. I had to swap RCA cables due to my old ones letting hum in.