I've been running a Bushnell TRS-25 on an AR and also ran it on my .30-30 for a while. It has held up to recoil, drops, a quick dunk in a pond while crossing a beaver dam, and some rain. I bought it with a rebate that brought it to $75.
Pretty impressed with this little sight so far. I don't have a rail on any of my shotguns, so I haven't tried it on a shotgun yet. Seems like it would make a good turkey sight.