Personal preference is quite a big factor, SNB. After trying a few options, I prefer the Sennheiser S1, which does have a high level of passive attenuation as well as ANR. ANR is great at lower frequencies, where most of the energy is in light aircraft noise. But there are components at other frequencies too and, to my ear, I prefer to isolate my ears from those as well. In passing, I note that the S1 feedforward optimization (done with a button on the left earpiece) pushes the ANR out to higher frequencies.
Comfort is quite a big thing, though. Important to try a few designs, and find one which works for you.
Re hearing protection, it is supposed to be an algebraic sum of pressure waves on the eardrum so where ANR works, it should be OK. But psycho-acoustics is a funny thing and I've also found the ANR experience can be a bit tiring (less so with the S1, I personally find).