If you regularly use your cellphone in the car, but so far have been reluctant to either fill the cabin with wires from an untidy aftermarket kit or are disappointed with Bluetooth headset performance, Sony might have the solution for you.  The MEX-BT5100 is a replacement head-unit, with the usual radio, CD player and MP3 CD compatibility as well as Bluetooth and an onboard phonebook for use as a hands-free speakerphone.

CNet have been putting the BT5100 through its paces on the open road, and come away impressed; rating it ‘Excellent’ (with a score of 8.3 out of 10), they praise the straightforward control - via a joystick and sturdy, tactile buttons - a clear and easy to follow GUI, and ID3 compatibility to show MP3 track information.The MEX-BT5100 seems like a pretty good way to spend $330. Via phonemag.com