Sound quality OK. Usability NO.
Purchased these and tested while sitting still and they were perfect in terms of fit and sound quality. As soon as I started walking around particularly in busy areas, most notably train stations, the audio in left ear would just drop out for a few seconds constantly. Updated drivers and even got replacement set and it made no difference. On top of that, if you like to watch video then you will also notice significant delay of 1-2 seconds between video and audio when using these.
Overall, if you're using these just for audio and only using them while at home or at a local gym where interference is minimal then they are great.
If you want to commute with these and you work in busy CBD areas or if you watch video then these are definitely not for you.
(I eventually had to return them because it got too annoying.)
Verified purchase: YesCondition: New