As I understand, noise trials found that the Bose headsets did have a good noise cancelling effect, however, when it came to high frequency noise attenuation (especially the high frequency noise that does the damage to your hearing and is above normal hearing range) then they were no better than any other cheaper headset. The noise cancelling earplugs, that Sox6 mentioned, do work and cut out the high frequency noise, however, not everyone can get on with them.
The choice is yours.