Yeah good tip about the mic socks, always a good idea for helicopters.
Also you can adjust the "gain" on the mics, we do it with all brand new David Clarks, its a small flat-blade type screw in the mic itself. Wind it all the way out (as in anti-clockwise, righty tighty lefty loosy) and it cuts down on the background noise you hear with the voice.
Again, very important for helicopter headsets due to the high ambient background noise.
The good thing about David Clark headsets over peltor is the ease of changing the mics, bloody peltors have to be soldered!