Neil: I'm anxious to hear your review about the Dillon HP1's. Did the loud noise cut-out of the peltor's bother you? It would seem that is the main advantage to the Dillon product. From the pictures it looks like the HP1's aren't adjustable to the wearer's head. Is that the case? It might just be that i can't see the head band adjustments from the picture in the Dillon catalog.