I am severely hearing impaired and without my high-powered hearing aids, I am nearly deaf. This caused me some problems when I got into 3-gun this past year because a big part of action shooting is being able to hear not only the start beep but also range commands. (And yes, in case you are wondering, I DO still need to wear hearing protection.)
After a lot of work and trial and error, I found something that worked. The MSA Sordin Supreme Pro fit the bill, but for a different reason than I expected. I originally purchased it because the volume goes the highest, but this was still not enough to allow me to function normally without my hearing aids – they weren’t loud enough. However, they WERE able to very comfortably fit over my hearing aids. With the added ear gel padding pack, they were comfortable as they were going to get.
They still get hot and kind of uncomfortable, but they allow me to compete normally.