I am using the DS970 with a SE K790a phone and so far it has been great. For comparison purposes I used a set of Sony MDR-NC11 to compare earbud sound/noise cancelling qualities and SE HPM-82's for remote/handsfree functionality. Using those two leaves you with almost 8 feet of wires and three modules to contend with, the DS970 got rid of that. The volume is louder with the DS970 vs NC11, although the noise cancellation is not as effective. It still however blocks out the majority of ambient noise, and works well in NYC subways. SQ wise is on par with the NC11's though don't expect audiophilic quality (remember it was made for noisy environments). The silent hissing is not as pronounced as it is with the NC11's. For remote functionality, plusses are the backlit display and positioning of the controls (somewhat similar to the stick remotes found with Sony's MD walkmans). Unfortunately it does not have a clip and dangles freely. The mic isn't very good compared to the HPM, most callers complain about sounding "far", though reorienting the mic does help. Battery life isn't much of a concern for me, though 6 hours is plenty enough (the phone will only last for 4 hours of music playback with a full charge). The battery indicator is deceptive, showing full most of the time (~3 hours) then dropping rapidly afterward. No problems with the charger as the phone charger can be used as well (a plus of using a SE phone). It is more sensitive to interference than standard BT devices, and you will notice it (music starts clipping/dropping). Overall it is great for those who use their phones as a music player and wear ear buds all the time.