Sound: The sound is good but there is no point of comparison with my old Bose Quietcomfort 35 II.
Noise Cancellation: The only way to notice is if you replace the included tips for Comply. Forget about noise cancellation with the included tips.
Two defective pairs: After wearing them for a while (daily use) I started noticing occasional noise in one of the earphones. Finally, my first pair started making a horrible noise in the right earphone during calls: Returned.
After a few weeks of using my second pair, the same happened this time with the left earphone.
In sound quality there is very little difference with my old Optoma BLE 4, and the big $400 price tag is hard to justify.