Does anyone have trouble with the NC causing an uncomfortable pressure feeling in their ears? I've experienced this with prior versions of the QC's and it's been bad enough that I won't use them. For that matter, I've experienced this in a few cars which used ANC instead of proper sound deadening materials & design.
Do we know what type of battery is used in the QC35? If it's Lithium Ion, I'm out -- that chemistry of battery degrades amazingly quickly. In tropical climates, I've seen them last barely over a year. If it uses NiMH or NiCd, then I might be interested.
For now, still using my well-abused 10+ year old Sony MDR-7506 cans modified w/sheepskin ear pads + acoustic "sheet" to smooth some of the edge off the treble. The upgraded ear cups/pad setup on these provides better isolation than many ANCs, every single part is field-replaceable, they're cheap, and no batteries required.