I second the blueant Z9. the earpiece makes the callers sound perfectly natural. Outgoing sound quality is very good as well.
I own a Jawbone, and a few jabra's, and a samsung wep200 as well. the outgoing voice quality is best on the jawbone, and the noise cancellation is amazing, BUT the jawbone earpiece sounds so hollow and tinny! plus im sure i dont have to mention the jawbone is a pig when it comes to comfort. it will take you half the day to get it on your ear properly.
the jabras i have are terrible. bt125, 135, and jx10. all of them sound EXACTLY the same.....BAD
the wep200 is actually a pretty good sounding headset, inbound and out. its just uncomfortable, and cheap feeling.
I did not like the apple headset at all, i actually returned it the next day. sound was ok, but range is terrible. and dont make any sudden movements because the thing WILL fly out of your ear.
Z9!