I absolutely agree with Mr. Scary. I recently added a BFD 1124P to my system (Axiom m50's & SVS 22-31PCi sub), and after a few hours of setting it up to get a nice house curve, I A/B'd it with my wife (using the bypass on the BFD). We both agreed -- an amazing difference. The bass was much smoother. The BFD helped remove a hump in a couple of areas, the main one at 60Hz.

A nice thing about the BFD is all the pre-sets... I will soon setup at least 2, maybe more, for different types of listening.