I got a fairly inexpensive Caldwell model from Midway that work. I suspect the more expensive ones do a better job of passing quieter sounds with good fidelity like for hunting. I just wanted the shot sound reduction while hearing normal stuff and they work fine for that. Range commands and conversation are easy to hear. Works fine for .308.
I bought my fiancee’ a pair of Caldwell electronic muffs and he loves them. I got them for about $25 on Sportsmans Guide.