Very cool. Mine are quite simple and inexpensive Caldwells, but have proven themselves to be a worthy addition to my HD suite. My testing of these has proven their worth, especially in directional hearing, good for me as I suffer from some hearing loss. They are not, however, rated at 30dB, but, I believe, 24. No so good in that respect, but they will offer better protection than not using any ear pro. The Leights sound promising and I'll give them a look as well.
ETA: I have not read all the replies, as I'm quite sure there are many espousing not using ear pro, as "you probably won't hear the shot anyway," which is the normal claptrap and I'd rather not see it again.