Brilliant! Very clear and loud, simple to install and use.
The only drawback is that it has slightly too big range. When I am parked outside my house or even shop, I have to remember to switch the device off, as I am still within the range and if someone rings me, I can't hear anything on the mobile, as it still goes through the speaker in the car. Otherwise, when I am out of reach, it switches itself off within 10 minutes.
Otherwise I am pleased with it, so much that I have ordered another one for my Dad.