Well yesterday I found the device that cost me $31. Very impressive. It use our vocal chord and yes caller cannot here the background. Now whenever i ride, I just pluck it to my nokia 6230 and off I go. Advantage is that for nokia phones we got voice activation so I just press the talk button and speak whoever name i've program and it will call out without having me taking off my helmet or my phone from my pouch.
i bought it at this joo chiat rd bike shop near 7-11 there.