For me, it was “wow, this completely transformed the low end and was more than worth every dollar spent.” It made more difference to the sound in my old room than spending 3x the money on speakers. And the new room, being well sealed and in the basement, was a hopeless echo chamber without bass trapping.
And in cleaning up the low end, you should get far more clarity across the rest of the band.
And in cleaning up the low end, you should get far more clarity across the rest of the band.