My husband wanted a bluetooth so we did our research and based on the reviews, opted for this model. Turns out it was the right decision. The noise cancelling is fantastic, considering he's tried a few other models and I couldn't hear him while he used it in his car, windows down. But with this 510, I can hear every word. And he can hear me. I own the newer 520, which works well for me (it's a bit smaller but doesn't have the noise cancelling as good as this 510 but since I drive with my windows up, it works well for me). We've bought one for our son and just bought 2 more - one to replace hubby's 2nd 510 (he's pretty rough on it and the rubbery part that goes over the ear tends to eventually wear out for him) and the other to set aside just in case Plantronics opts to stop manufacturing this model. We've found it's good to get extra little covers for the microphone - over time they tend to fall off or get lost (did I mention hubby's kinda rough on his bluetooth?).