I took the standard issue BlackBerry headset and bought a three pack of the larger Jabra earpieces.....put the medium sized one over the plastic mic(took the foam piece off) and bingo.....I have to admit the OEM headset performs the best for me relative to sound quality.
How great are those Jabra ear gels? I did the same thing prior to getting my Jabra Ear Boom headset, I would still like to know what it is that makes the standard OEM Blackberry headset so much clearer then other third party solutions?