I have used several types of electronic muffs as well as Walker's Digital Game Ears BTE (Behind the Ear) styles.
They both have advantages and disadvantages, some of which is personal preference.
For me, the biggest advantage of the muffs is that they keep my ears warm. You really want a good pair, with dual microphones and dual speakers on each side so you get "surround sound". Otherwise, it can be difficult to tell direction. I do not find most muffs to be uncomfortable at all for wearing 4-6 hours at a time. The downside of them is the same as the upside... they keep your ears warm. For all those times you want to take your "hat" off because you're too warm... you can't do it with muffs or you lose your hearing protection. I've never found the smaller ones to interfere with gun stocks, but some guys say they do. Some people get headaches. I have an uncle who can't wear them for more than an hour or so without getting a headache.
The biggest advantages of the BTE style is that they're small and don't interfere with shooting nor hat wearing. My uncle uses these instead and doesn't get headaches at all. He finds them very comfortable. The biggest disadvantage of these is $$$. Good ones are at least a couple hundred each, if not $350. You definitely want digital. Also, some people have trouble with directionality with them too. They only have one microphone and it's behind your ear. It tends to make things behind you sound like your natural hearing would assume it's in front. However, overall, (and I'm talking the $$$ ones here), I find them to be very good directionally because your brain does most of the "math" just like it normally would... in other words, if a sound is coming from behind you to the right, the right ear will get the sound earlier (microseconds) and louder (consciously imperceptible) and your brain just "knows" that's where it's from. Another advantage of these is that unlike most muffs, you can adjust the volume separately... you can actually correct your hearing if one ear is weaker than the other. This can take some getting used to, as your brain as long since adapted to your broken ears.