Summary: Don't even think twice about it; just buy it. It works beautifully, has a long battery life between charges, is fairly easy to set up, offers clear communication in both directions, is very portable (take it with you when you travel and use it in your rental car...just dont leave it behind.). It does have a long range, like one reviewer mentioned, so if you park your car close to the typical location for your cell phone, it stays connected.
Summary: I love everything about it except the 30 meter range is too much. I have to turn it off every time I leave my vehicle at home as it stays connected from my garage through most of my house, making answering my phone difficult. This is the only reason that I gave it 4 stars, everything else about it is 5 stars.
Summary: I switched from a Treo to an iPhone recently. I drive a manual transmission so can't safely drive and talk without a truly hands-free kit. Earpieces I find distracting. I had purchased a TomTom which promised to work with my iPhone for hands free (the navigation was just a bonus for me) but didn't work at all with the iPhone contact list (no speech recognition). So I had to return the Tom Tom.
Summary: A friend had one and I have been looking for a hands-free that really works (clear conversations on both ends). Love this one. It announces who is calling having imported all the numbers from my address book in my iPhone. It's a winner.