I watched Kong at -7dBRef (Reference Level per se for my size room, with -0dB set at 85dBC calibration), and no bad noises, but I expected some flat tops based on the listening experience. Not as bad as the 'lunge for the volume control' as in Tron:Legacy, and DEFINITELY not as bad as Star Trek:Into Deafness....
According to MrEdge's graph, GoTG2 has less of a rolloff than the original. That is a good thing.
I do not use an LT boost anymore to watch films, as I get very little room gain in the new room. The Crowsons did get a workout, though.
JSS