Bose
I bought the Bose about 4-5 years ago or so... Been quite happy with it. I got it when I was in the right seat of the 727 and then upgraded to the Bus - I was planning on selling it when I switched planes, but discovered that many of the Buses are not that quiet. Some have very noisy AC packs. I have used it for quite awhile on 2 different planes and have been quite happy with the purchase. As for leaving it on the plane, knock on wood, I haven't. It is the FIRST thing I do when I pull into the chocks - remove headset, stow in flight bag, then doors.
On a comparison note; 4 years ago when I was in the Boeing, a captain with an on-the-ear style Sennheiser wanted to try my Bose, so we switched. I was shocked at how little the Sennheiser (on the ear vs. over the ear) did. When he took my headset off, he said if he had known the difference was that big he would have gone straight to the Bose.
Although I am a Bose fan, any ANR headset will go a long way toward saving your hearing. Roger - huh?
Goose17