Comfortable!  They work great!
I travel by air quite a bit, and sometimes, the noise level on the airplane can be quite overwhelming to me.  While I haven't tried these ear plugs out on an airplane yet, I did try them out near a lawn mower, a crying baby, and a very loud television and found them to be quite effective.  They're comfortable, unlike some of the foam ear plugs I've tried.  I love the case they came in!  The case can be easily attached to a backpack or purse so they're easy to find when needed.
Rating: 5 stars