I always use one or the other when exposed to loud sounds. I keep muffs handy while using a circular saw, because I only need them for a short time. For longer continuous use, like a concert or a long shooting session, I use earplugs. I always try to use the ones with the greatest noise reduction. I found a bunch of foam earplugs which I think have a 30 decibel reduction. I think I will try plugs and muffs next time I shoot.
Between military service and numerous rock shows, I have to save my hearing. My girlfriend's brother in law lost his hearing after 25+ years of construction. He now has hearing aids in both years, and he's my age of 42 years.