I offer the following as an anecdotal data point only.
I have a 1301T set up with the Aridus Industries forend, stock adapter, and Aimpoint CROM mount. It has the Magpul SGA stock, as well as a SureFire M600 and a Wilderness Giles Sling. It formerly had an Aimpoint H2 on the CROM mount. I had a few hundred rounds on it in this configuration. I took one of TCinVA's classes with it last year. I had not fired it in a while. Back in April I took it to a local indoor range to shoot the Virginia DCJS shotgun qualification. This is a ridiculously easy course that involves shooting five slugs at a Q target. I fired the first slug, and as the gun came out of recoil, I noticed the dot jump dramatically to the right. It had formerly co-witnessed with the irons.
It moved enough that when I fired the four successive slugs using the dot, they were barely on the edge of the target (the paper not the bottle). I took it home and played with it, and I was able to adjust the turrets to get it to co-witness again, but I just didn't trust it.
So I took it off and dug out the box and sales receipt. I had purchased it about two years prior.
I eventually called Aimpoint USA and got an RMA number. It took me a couple of weeks after that to get around to sending it to them. I finally did. My package was delivered on June 14th. On June 21st, I got an automated e-mail saying my ticket had been closed. This morning I wrote back to ask what that meant. The reply I got was as follows:
I take this as a good sign that Aimpoint identified a problem of some sort and are working on it. I am being patient, as I have other guns to rely on, and I want it fixed correctly.We have your sight and it is in Sweden now being serviced.
We should have it on its way back to you shortly.
The big question I am wrestling with is this: Is 12 gauge recoil just too punishing to use a red dot at all? If it kills an Aimpoint, maybe that is what we call a clue? Maybe I should just use irons?
I own a number of other Aimpoints (as well as numerous conventional optics), and this is the first one that has ever failed.