I use my QC20i while flying, at work, and occasionally at home. They are the first NC headset that I am comfortable using. The over ear types just feel weird to me, giving me a feeling of someone clamping down on my ears.

FWIW, often, I'll use the QC20i without the NC Circuitry switched on. The noise blocking itself is adequate for most places, and having the NC turned off does not drag down the audio output unlike some headsets.