first of all, i thought they were named anr for reduction and not cancellation (although a 'c' in the abbr. would have been fantastic). be that as it may, i have one thing to say about the bose vs david-clark: 12 oz!
it is fantastic. try wearing a d.c. headset for eight hours straight.
the downdraft with the bose x is changing the batteries every fourth-fifth hour.
cheers
tigerpic