The electronic part of muffs adds nothing to their protection. That is provided by the construction of the muff. Most all electronic muffs that are thin enough to not hit the stock when I am shooting do not have the level of attenuation that I am looking for, but then that is true of non amplified muffs as well. The advantage of the amplified muffs comes with their allowing you to hear range commands better through plugs when using double coverage. Generally this is not an issue for me. I use the 33 db rated Howard Leight foam plugs in combination with some old muffs that are probably no better than the thin Peltor shotgun muffs that have a 21 db rating. What I rely on for my hearing protection selection decisions are my ears. I hear significant differences between various products and combinations. Another thing that I pay attention to are after effects, any slight temporary increase in tinnitus after a range session, or or other discomfort. I have custom molded plugs, so I can speak to that option from experience. In the last couple of years I have done a little innovation that is entirely out of the box in how i use the foam plugs. At some point I finally figured out that I was not getting a proper seal at the outside of my ear canal from the foam plugs, and while inserting them deeper would solve that issue, it created a new one...getting them out. To solve that problem I came up with a simple home made modification, that gives me a "handle" that does not alter their attenuation. This gives me the best of both worlds, the advantage of deep insertion and ease of removal. There is one other product that I see has not been mentioned, that I have found works remarkably well, even though it looks like it would not, and although there design precludes use with foam plugs inserted to normal depth, by using my modified plugs I have been able to double up, producing an eerie silence that has to be experienced to be understood. This is what I am talking about.
https://www.amazon.com/dp/B001IMHSP4/?tag=accuratescom-20
To get them to work as designed, I find it necessary to put them on the way that the manufacturer recommends.
Beyond preventing hearing loss, which is of course the primary concern, I find that maximizing attenuation helps my shooting, reducing the risk of involuntary reaction to loud noise, allowing me to be more relaxed.