I bought these ear plugs to see a band, a loud band of course, and over the years I've not been happy with the ringing in my ears the next day. I wanted something to protect my ears.
At first, when I tried them out at home, they hurt a bit. I am a small girl with small ears, but I think they hurt only because I was getting over a cold and my whole head was still aching.
When it came to the gig however, I put them in before the music started and there was a little discomfort at first but after a few minutes they were fine and they didn't bother me all night. I could hear the music so much better with them in, the sound of the crowd beside me was filtered out to some extent, but I could still talk comfortably to my friends. I took them out for a minute for the last song to see how they worked, and the music was a lot louder/harsher/noisier when I didn't have them in.
One more thing, the ends of the plugs stick out a bit from your ears. I was worried they would get knocked out or even worse further in to my ear, but they were fine. I wouldn't want to wear them in the pit though I think that they could get bashed in by accident.