At first glance the Bluetrek SurfaceSound Duo seems an eminently useful idea. Clip it to your car visor and when you enter the vehicle just pop your headset into the slot to get a handsfree voice system for your mobile phone. It’s only when you think about it a bit more, and realise that a headset offers more hands-free voice clarity and convenience than this thing can ever provide, that you realise this is a product without a reason for existence. And then, if you’re like us, you start to feel a little sorry for it. Luckily the video makes it look a little more reasonable. Almost.