I would be skeptical if Leupold, Burris, Trijicon, Aimpoint, Vortex, Holosun, Sig, Crimson Trace... didn't all last at least xxxxx rounds. Basically, I would put forth the conjecture that if you buy a reflex sight that is at least $200 Amazon, Midway, OpticsPlanet etc. price, then it can be expected to last well over 10,000 rounds without an issue -- probably closer to a six-figure round count, but let's face it, not many people are going to test that. We discussed losing screws in another red dot thread recently. They must be torqued properly, preferably with an actual torque driver, and anaerobic threadlocker (Loctite) must be used.
Now there are some red dot sights that were always made for frame mount and not slide ride. The Leica Tempus or the Noblex C Sight for examples. Presumably great sights from high-end brand names. But you could kill them on a slide because they were not made for that. I also suppose there's sub-$200 junk that will work for plinking but die after a couple thousand rounds.