Are you looking for just any BT headset or a stereo headset for music as well? I used to have Moto HS850 with my SE K750i, and it was a disaster. Nobody could hear me clearly even when the volume was at max... Then I tried it on Panasonic X70 and they worked as a good match. I heard no complaints ever since. I was guessing it had to do with the phone then. My friend just bought the i.tech R35 for me, and I will try this with my P525 in a few days. I can let you know how it comes through for me if you are interested.