I tried one out a little while back and was pretty dissapointed in the ANR. There was no audible difference in having the ANR on vs. having it off. Makes me wonder if it even exists. I guess there is a reason why all the other ANRs have batteries and loads of electronics. Other features of the headset were nice. They were comfortable, did a relatively (for a non-earcup style headset) good job of passive noise reduction, and the microphone seems to perform well.
If you want to be able to hear when you retire, get a full earcup ANR headset. If you want to be stylish and not mess up your hair, get a telex 850.