BlueAnt S4 Bluetooth Car Speakerphone Kit [USEN-BAW-S4]
After reading about various Bluetooth visor mounted handsfree units, I decided to buy the BlueAnt S4 unit.  After 3 days of trying to use it, I have given up and returned it.  Problems:  1. it can't reliably respond to a command to dial a given name in my iPhone contact list.  2. once it thinks it has found the right name, it immediately starts to dial- even if it is the wrong number.  It should ask you (Yes/No) if the number is correct or not before dialling.  This is terribly frustrating and embarrassing 