Parents, do you let you kids listen to music with a parental advisory?

We didn't think it was a big deal but music these days is getting pretty rancid. We have a 12 year old and a 14 year old. Yesterday we caught them listening to some questionable music and we confied it. Of course one on of the CD's had a 2 paragraph long parental advisory it's so bad. When they are 18 they can listen to what they want...But who would even want to listen to bands with names like Cannibal Corpse or Charlie Molester...Just rancid, offensive music.