I bought a set of the molded plugs back in 2014 when the dealer was present at a GSSF shoot at St. Augustine, FL. Friends that I shot indoor IDPA shoots swore by them for pistol shooting because the blast is much closer than with a shotgun. The vendor there was selling them for $65 and that was much less than what my friends had said they paid for theirs.
I was able to get the custom plugs made before I shot my entries in the shoot and was very happy with them(but not my shooting). I don't believe it would be worth the money to buy them for shotgun shooting although I use them often because my sonic plugs have a tendency to fall out
