Honestly, it's rubbish. Yes, even at over 9 grand with the extended warranty. They are hugely unstable and behave even worse than previous generations. Unfortunately, despite all the ills, they are probably the only headphones that fit small ears, that do not hurt ears even after 3 hours, that do not cut your ears with the sharp end of the blades when you turn them to fix them, that can suppress noise and hold the stabilizing bands, so when running to the train they do not fall out of the ears like Sony WF-1000MX4 or 5. Unlike the Sehnheiser Momentum, the touch controls don't go crazy in temperatures around zero and start turning off, on, and scrolling through your music. But don't be under any illusions, double and triple presses to move a song cannot be used, because in half of the cases the number of presses is evaluated wrong. Especially if you have cold fingers. The sound is very good, but don't use the microphone to make phone calls. You won't be understood, and if a car passes you, the person on the other side will lose their head from the noise. The headphones occasionally don't connect or stop working to mute songs when removed from the ear, or even touch controls in general. Sometimes the handset shuts down (firmware crashes) and needs to be restarted by putting it in the box. Pairing is a nightmare, it connects to the app stably for maybe the tenth time on both Android and iPhone. I had an earlier generation and we also have a Bose SoundMicro speaker and they are all equally unstable. It's the firmware. They behave worse than the previous generation QC II, where after a year one earpiece went out and never came back on. Because the service did not even comment on the complaint within 30 days and the headphones were no longer sold after a year, Alza refunded me the full amount, for which I had no choice but to buy this newer version. It's sad, but even at this price, you can't get any small-ear headphones that hold, noise-cancel, and are more stable. I had written a more detailed review, but the Alza Android app closed the window when correcting typos and all the text was gone. So don't be mad, but I'm not sitting here for an hour again.