I've been using Red Dot sights on my 12 ga. shotguns for years, the only time they've ever broken or cracked lenses is when I would let others shoot my guns 'it always happens to new/inexperienced shooters'. They're afraid of the recoil - so they don't have a good grip or stance and when they fire, they always allow the gun to almost fall from their hands. The recoil has to go somewhere when they don't have control of the shotgun, so I've never had problems with failure of a Red Dot, but I've had 3-over 20 years Blow Up on my shotguns.