If I were in it just for music, I'd go with the LV12R because one has a bit more control and unless expecting to be reproducing 16Hz notes such as what is produced by a pipe organ, depth of extension is not important as it is with Home Theater. IIRC, a double bass guitar only goes to 31.5Hz. The constant servo technology feedback and the tunable nature of the FV15HP, expectedly will give tighter/more desirable musical qualities.
The problem, at this price level, one is expecting a great deal of these subwoofers and there's an excellent chance one will run into disappointment. In my opinion, true musical bliss will be found in the subwoofers that use the more expensive drivers such as what one would find in higher end sealed subwoofers such as a pair of SB-2000 or a pair of high end sealed Rythmik subwoofers.
My understanding, sealed subs for smaller rooms and depth of extension.
...........................ported subs for larger rooms and output.
Higher end drivers, amplifiers with higher output so the amplifier isn't going be driven into distortion and features which allow one to better tune the sub to match the acoustics of the listening venue. It never hurts to have high end EQ'g capabilities such as what one will expectedly find in a XT32/SubEQ HT equipped AVR and have at their disposal, an up and running copy of REW so as to be able to see the interaction of the subwoofer's output with the acoustics of the listening room.
Just saying, quality sound does not start and end with the simple addition of a quality subwoofer.
Bear123 posted this review link for
the PB-2000
And theJman did a review of
the LV12R.