I have not noticed any change in sound quality from the original headphones, nor had any issues with their quality or longevity as mentioned in other reviews (although I have not done a back-to-back test), so all good there.
However, the people at the other end of the phone often complain that they can't hear me, so I have to remove the headphones and use the phone conventionally.
The headset also does not control Apple devices so you have to manually control your phone / iPod etc if you are using that.
Overall, not functionally great as phone headphones, but sound is fine and with much less cable noise than from the original supplied cables (these are soft finished).
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