ANR Headsets suitable for heli pilots in training?

Hi all,

I am a student pilot, working on my PPL-H right now, and I have 6 hours
in the R-22 so far.

I have considered purchasing a pair of Active Noise Reduction headsets,
Bose or Sennheiser etc (haven't compared them yet). However, the chief
flight instructor at my school says that he doesn't recommend ANR sets
for trainee pilots, as it is important to learn to listen to and
recognise the different sounds emanating from the engine as well as the
rotor when flying. He feels that ANR Headsets might get in the way of
that.

What do you guys think about this? Are ANR headsets something only
experienced heli pilots should use, will they get in the way of learning
to "read" the sounds coming from a helicopter in flight?

Your views or comments would be greatly appreciated.

Regards,
John D.