Zulu's for 14 months in commercial ops and faultless.
Although I don't buy Lightspeeds advertising spin that the earcups being made from the same material as SR71 gear doors (titanium) gives them superior passive noise reduction.
When the batteries go flat they are on par with Bose and completely useless, I swear they actualy incourage and propagate a certain frequency within the cups so the ANR has something to chew on and look (sound) like it's working.
As always, any comments made by Americans needs a degree of skeptical analysis.