i,m looking for handsfree for iphone 4s, which one is the best for it

I really like the Plantronics Voyager Pro bluetooth headset. I have tried a lot of the ones on the market and the Plantronics one that I now use has - a long battery life, excellent sound quality and very low background noise. I occasionally use it when in a vehicle (although I do try to avoid doing this) and people on the other end of the line don't even realise that I am in a car.