The ANR upgrade kit from Headset Inc is awesome! Cost me $169 I think. The customer service was excellent as well. I ordered the wrong part (my fault) and they sent the correct one out (with no shipping charge) before they even got the original one back. Great people and a great product in my opinion. I know a lot of others that have them that recommended them to me. I upgraded my Clarks but the kits are available for any major brand headset.
http://www.headsetsinc.com/
