esp, esP, eSP, ESP!
I have used esp exclusively for the last 2 years on the sporting clays course. They are very comfortable and they work quite well. The key to success is to keep them clean. Jack is very easy to deal with.
I know, it's only a shotgun. Wrong, almost every shotgun on the range these days is ported. Stand beside a ported 12 gauge with marginal hearing protection and you will feel the pain.
I wholehearted endorse esp. They are expensive, but for the comfort and quality, there worth every penny.
I've tried the various electronic "muffs", and they all get in the way of mounting a shotgun or rifle.
By the way I shoot 15,000 to 18,000 shotshells per year and have no problem investing in whatever product works best. For my money it's esp.