I’m closing in on 20yrs with one mounted on my 870 Marine Magnum. I installed just as it came from XS a few days before my first shotgun class with Louis Awerbuck (RIP), ran it in my 2nd class with him & toted it all over Montana where it was loaded with alternating 3” magnum buck & slug. Hell, it’s outlasted both my marriages…but I could just be lucky.