For starters, I'm new to the whole noise reduction earphones. I've been using my default iPod and iPhone earphones for some time now and these Skullcandy ones are miles better. They block out all but certain noise pitches and they come with extra silicon ear buds.
The headphones are great too! These are better than my Sennheiser headphones as the sound is more rounded. My Sennheiser are very bassy in comparison and don't convey the full experience of my music.
All in all, I rate these highly.