I have been using PMMN4071A noise cancelling RSM's on XPR3300 radios, in analog, in an industrial manufacturing environment. I have been less than impressed with their reliability and actual usability in the environment. In digital, running basic noise cancelling with a windporting (PMMN4073A) and RX Audio Leveling seemed to give the best audio. I was having low audio volume issues when I did the testing, that I have since fixed and have not re-tested.