I was a user of scala, worked pretty fine for me. But then I sold out scala and bought interphone F4. I have made a biggest mistake. I
have wasted a huge amount, just to buy that cheap product. I was facing many problems with this device, including the voice quality
problem. When I went to return this product (the interphone F4) Blueant were a nightmare to deal with. I would not recommend this
product to anyone ? the voice quality is pretty bad. Try a can and a string ? it would work better.