"Great design if you want to use your own headphone."3.5 starson by sfsailor
Pros: Detachable ear phone design lets you use your own headphone. In my case, I am hooking it to my car stereo and whala, you got a car stereo can play music and do phone calls. The clip is handy too, I just click it on my air vent grills.
Cons: Multi use button too small, and not very obvious when pushed. Charger cable is too short.
Summary: If you wan to use your own headphone, it is the best. I cannot figure out why there's no one build such thing just for a car stereo yet. Although it works in basic functions, i.e. play music and take phone calls, I wish it as a screen that can display song names and phone numbers. Of couse that will make it much bigger too.
Anyway, if you want a simple, poor man's bluetooth kit for your car, this will do the job.