I had QC15 for over 7 years and QC35m2 now over 3. Both used and abused because I don’t really care about the case. Never broke anything in them. Eventually l

I had QC15 for over 7 years and QC35m2 now over 3. Both used and abused because I don’t really care about the case. Never broke anything in them. Eventually lost the QC15 and upgraded to QC35 - a decision I never regretted even though I fly way less now and use $600 audiophile headphones. Fantastic headphone - research the analytical tests, the QC has almost flat response and the noise cancellation makes it very pleasing to listen to. YMMV.