Often, when visiting BB, I will hear rafter-rattling bass from someone "testing out" (more like maxing out) one of the subs. I would not want to get one that has been treated that way.
LOL, yeah I have seen them treated so poorly, with kids poking things in them.
I have seen one that the entire driver was kicked in....
So if you buy it used from them, it would be pretty safe to say that it may have been through hell (whether testing by bass heads, or with being roughed up from even the workers).
Personally, I would pass on buying used floor model speakers from them (unless offered at a superb price, with full warranty).
But, I have bought used electronics from them, although rare. (and have had no problems in the past).