I think I mentioned during one of our conversations that I played my GenIII's loud enough during the first 100 hrs. that I couldn't stand to be in the same room with them & not because they were so loud, rather they just sounded so bad. I would guess in the mid 90 dB range & now 3 yrs. later they can play 105 comfortably at the listening position w/o any problem whatsoever. I would think the same set of rules apply to the jr's too. You can always call out there & talk to them about it.
Once I got past those first 100 hrs, I just did what I do now-sometimes I play it loud, other times at the lowest audible level.
My listening position is 10' from ea. spkr