The sound quality of Sony is as high as usual. Noise-cancelling functions quite well and could adjust autimatically as per the soundings vary, which provides lots of flexibility and convenience. Also, in comparison to other earphones, it hardly drops when I am doing some cardios, which I highly appreciate. Yet it is hard to know if it requies charging unless wearig it. I expect the battery level could be visible in the coming versions. I also expect it could be even lighter - this is very importatnt when I need to wear it for a few hours online meeting.