.
Picked up a pair of these
http://www.amazon.com/Howard-Leight-R-01526-Electronic-Earmuff/dp/B001T7QJ9O on the recommendation of the Mad Orge blogger and gun shoppe owner. Like 'em a lot. And they go for a good price. The muffs are thin, and pose no problems for mounting the stock of a long gun.
I can clearly hear the instructions in an indoor range and still not be deafened when someone shoots their atomic hand-cannon next to me. (Are there really that many grizzly bears in the L.A. Basin?)
One thing: The earmuff has a port for plugging in a radio or iPod. That feature never worked for me. It didn't bother me enough to take the muffs back to the store and get another pair. So I don't know if it is a flaw of my unit or the entire design.
Man, I'm having problems with the GRRN server..... Think we need to get Mark some more cash....