I bought this to comply with California's handsfree law. I made sure to purchase from Amazon directly because they guarantee that the product is made by Motorola and is not a cheap imitation. Be careful that your seller is Amazon and not another vendor selling through Amazon if you want this guarantee. I saw on the Motorola website that they have had significant problems with this model being copied and I decided to pay a few dollars extra to make sure I bought the real thing from a reputable vendor.I use this with my Sony Ericsson W580i (which I love). Set up was extremely easy, they recognized each other instantly. The sound quality in the headset is crystal clear. I keep the phone in the car console beside me and the sound in my ear is loud and clear. Everyone I've talked to said they could not tell I was using a headset. I have been using this headset for 3 weeks and I have NEVER heard any static. I believe that the bad reviews are probably due to people who bought fake Motorola headsets. They could not possibly be talking about the same headset that I've been using. When I first started using it I pushed the button when the headset was in my hand and I was sometimes confused about what it was doing, however, I have learned that it's best to push the button when it's on my head because the confirmation tones let me know exactly what it's doing. I was worried that it has only one function button(not including the volume buttons) but that hasn't been a problem. It uses smart context logic and, along with the confirmation tones, one button seems to work fine.I wear glasses and have found that if I rotate the headset a little clockwise and counter-clockwise as I'm putting it on, it always nestles into a good spot and cohabitates with my glasses just fine. The ear piece clamps down on my ear just right and feels pretty snug. If I move my head a lot it does flop around a little but it would take a lot of activity for it to fall off because it's gripping around my ear pretty securely. I really didn't want something actually sticking into my ear like earplugs. I love how this has a tiny speaker that is held just next to my ear without actually going in my ear.I set up my phone to use voice calling and recorded the commands using the headset. It was easy to do and works great! Now I can press a button on my phone, then say the name I want to call, the phone plays back my original recording (of what it thinks I said) as it places the call. I hear all of this happening through the headset.The only thing I don't like about the headset is that I don't seem to be able to change the ringtone. It has a gentle, short, classical music tone when there is an incoming call but I can also hear the ringtone from my phone so I do know who is calling. One short button press on the headset and I'm talking to my caller.In summary, this headset has amazing clarity and is easy to use. I'm glad I didn't pay for a more expensive headset - I don't feel like I'm missing anything.