I have tried the VOX function on 3 different radios, ranging from 60 to 220 dhs, and played with the sensitivity settings, but could not achieve reliable results. It only starts broadcasting when you start speaking, so half of your sentences will be lost. It works however quite good in office environment where you have less background noise.
I have also tried the earpiece but again the sound quality is not super, and you need to push the button on the wire anyways to broadcast.
For now i have attached a lanyard to my radio, and it hangs around my neck so it's easily accessible when needed.