I use a set of Walkers Power Muffs. They don't shut off at the gunfire - they use a sound compression circuit. So I have no trouble hearing someone talking to me with gunfire nearby.
I don't use them at the indoor range. Simply not enough noise reduction - even with foam earplugs underneath. If we had a dedicated rimfire indoor range, it would probably work - but the rimfires share the same room with .45acp, so I go with the earplugs & conventional Leight muffs over that.
My local outdoor range has no roof, so the Power Muffs work fine out there. I get the most use out of them in the field, though. When hunting small game & varmints, I find that having the electronic muffs on works very well. I hunt with the handgun a lot, and even with rimfire hearing protection is a must. Using the muffs, I can still here my prey (sagerat safari!) - and my shooting buddy talking to me from 50' away.
There is a temptation to turn up the amplification with these for that "bionic ear" effect. I don't do it (anymore), because you start hearing things that are so far away as to be distraction and irrelevant to the task at hand. Besides that, it causes certain sounds (especially aircraft) and speech frequencies to be a little distorted. It's best to just leave them so sounds are normal to just slightly amplified (I do like to cheat a little
).I've heard some guys saying that the electronic muffs would be annoying in the field because wind noise and your footsteps will cover all other sounds, but this simply ain't so. Wind noise is what it is, even without the muffs - and if you keep the volume to reasonable levels, neither that nor footsteps will be a problem or even a distraction.
Bottom line - I like 'em - but not for everything.