"In my opinion those headsets are poor and I've bought my own Sennheiser HMEC25 ANR (closed cup). The difference to the open cup is day and night and it's comfortable enough even on long sectors."
Our airline's flight crews use these, too (Or a variation thereof... HMEC25BAQ).
"You will only be wearing it for short periods in climb and descent..."
I was under the impression that cruise was the noisiest part of the flight on the 744, due to wind noise at high mach numbers???
A while back, there was a problem hearing TCAS alerts with the headsets on and the crews had to keep one earcup off until a certain altitude. Unfortunately this induced some kind of vertigo. Not sure what the outcome of that was.
Rgds.
NSEU.