I bought my QC35s in the Bose shop in London, and got a few hours out of them on that trip, but at the airport before a 19-day jaunt around the USA, the on/off/bluetooth switch broke, it would just slide frictionlessly across and back. I need NC, so I picked up a pair of Sony MDR-ZX770BN at the airport. I immediately noticed the difference between these and the QCs. The NC isn't nearly as good (I actually brought them back to get some advice as I didn't think the NC was working at all) - I tend to listen to podcasts 99% of the time, but the QCs are definitely better at blocking out bg (airport) noise. The Sonys also felt bulkier and plastickier.
And now the happy ending
. I popped into a Bose Outlet store while I was in the States, and showed them the broken switch. The guy told me the stores weren't linked, but he did something on his machine, and then gave me a brand new out of the box pair of headphones and the audio cable which had been attached. No questions asked, no proof of purchase, no registration (I hadn't had time). I'm now being a little more careful with these ones just in case they go the same way, but I used them on several flights, and absolutely love them. They're now attached to my PC and my only regret is that I don't travel more than I do.
So anyone want to buy a pair of Sony headphones?