On the strength of the overwhelmingly positive reviews I went out and
bought myself a set.

Yes, they are pretty impressive. I was struck by how much the actual
experience of wearing them in a plane matched the experience I had
trying them out at AOPA Expo in Bose's noise simulator (which I thought
seemed a bit cheesy at the time). Switch on the ANR and low frequency
engine noise vanishes almost entirely. It borders on being eerie.

However, I noticed that while the Bose headsets are objectively much
quieter than my old Peltor non-ANR headset, the *subjective* experience
of wearing them after a while is not so different. I think this is
because the human ear has a certain adjustable dynamic range with
something akin to an automatic gain control. It only took about 10-15
minutes before I really felt like I was hearing just as much noise as I
did with the old Peltors, even though I knew I wasn't.

All in all I'm not sure they were worth five times what my Peltor set
cost, but so far I've only worn them for less than an hour. I may
change my mind after a long trip. I'll let you know.

rg