Looks nice, but I have to remain skeptical about this one.
I've used Jawbone Bluetooth headsets before that used bone conductivity technology and was not impressed. And those Jawbone units were built larger and had an actual earpiece to help keep it in place. Twisting it constantly won't be good for it either. Sometimes with Bluetooth earpieces smaller isn't always better. Maybe it will work well, but I can't see how.
SGH-I337 (AT&T) 32GB
P-ROM (1st Gen.), De-Odexed, AMDL
Auto-LOKI OUDHS CWM
Make sure you read and understand the "PINNED" threads in the "General" and "Q & A" sections of the AT&T S4 forum BEFORE you ask for help. Use the forum's "search" function to find posts with additional information. You should not expect others to help you if you haven't tried to help yourself first. Also, read, understand, and follow the "XDA" rules.