Great review and commentary. Makes me re-think me long-held doctrine of iron sights only. The idea being, can I throw this rifle on hard ground, pick it back up and still have the same working sight picture? That tends to eliminate most of the optics out there. So, in terms of durability and mounting systems, how do the Trijicon and Eotech products hold up? Given their service history, I’d have to think - pretty darned good. Sounds like the Elcan C79 sight might be what you're after. The Canadians mount them on their C8 versions of the M4 carbine, and the USMC has been giving them a try on the M240 MG, since lesser units don't hold up well to such use on full-auto beltfeds.
I think the sight would still be usable after the sort of treatment you describe. The rifle might not, but I think the sight would still be in zero.
"Makes me re-think me long-held doctrine of iron sights only. The idea being, can I throw this rifle on hard ground, pick it back up and still have the same working sight picture? That tends to eliminate most of the optics out there. You aren't kidding. But I can attest that the TA31 can be dropped onto concrete from five feet and not only stay intact but maintain zero.
Please don't ask me how I know this. $:-)