First off I wish I knew about Adire before Rockford. The big misconception is SQ. All subs sound the same. There is no SQ under 100Hz. The only separation, is how each sub handles those frequencies at a given power level.
At low power they all sound the same (I am talking about decent, meaning not flea market brands). So the Tumults don't kill the RF at SQ and wouldn't do it for any other sub. I haven't tested, but the Tumults would destroy my RF at near max power at low FS's. The Tumult has more force at FS below 20. But that is not a fair comparison, because the Tumult has a natural FS of 19, RF is 24.
Once people realize this, there would be no more of, this sub is SQ and that sub isn't. Like I said, now that I know about these internet company's subs, I'd rather spend my money on them, cause they seem to put more work into production quality. I wouldn't recommend commercial brands anymore, but I will never knock them either, cause they get the same job done.