I use my phone constantly while driving AND have a moderate high frequency hearing loss. The 655 DSP is perfect for both. It works seamlessly as it is advertised to do. It fits my ear without the wire hook and stays all day. It is so light I totally forget I have it in. The earmold design is very efficient in delivering sound to the audio canal. I usually push it in as I recieve a call but that is not really necessary. The sound quality it delivers is VERY GOOD. I understand as well as with my $1800 hearing aid (that I remove in favor of the 655 DSP). Battery charge life is excellent. The controls work just fine (I had to get used to them). I totall recommend this unit. It surpasses the other 2 units I have used by around 250% or more.