This is a quote from Scott on the SSA forum about the Q with BP option:
"There is a little spec change on the drivers as we are adding a little more suspension stiffness (although we are swapping stiff spiders out for more soft ones too). The subs stay a little closer to their original suspension values and have a slightly increased qts, fs, and reduced vas. Not too much of an issue and I have found it to be beneficial in most bassrace setups.
Now this is not something for everyone and I dont think that most people need to add it. But we are getting more and more bassrace applications where being able to stack more power to ge the sub to its linear limits for a specific application requires more than the rated RMS power (often quite a bit more) and this option allows you to push things a little harder for some applications. If you are looking for a SQ setup or just a clean daily setup within the normal limits of the subs... then there is no point.
Would I recommend it to someone with 1200W in a daily driver? I doubt it as it really wouldnt be needed and the extra 200W really isnt an issue. Its the guys that are trying to stack on 1800W and push them as hard as possible for 30 seconds (or try to all day) while voltage starts to drop and things start to get ugly towards the end."
Makes me wonder why guys are getting the BP option for a daily driver....