Maintenance is zero if the sights are
- Quality sights with known long battery life
- Battery replacement is done at a frequency relevant to how you use the sight's brightness settings
- Installed with the correct screws, tightened to a torque appropriate to the screw thread specs and the material of the mating threads, and with medium strength thread locker.
Which brand of red dot is on your VP9? When was the last time you changed the battery? Is it always on, or do you shut it off when you store the pistol? If it's always on, is it on a fixed brightness or are you using an auto-adjust brightness setting (if available)? What size screws mount your sight to the slide (or adapter plate)? How much torque did you apply? Did you apply thread locker? Are the screws the right length? Too short of a screw and they won't generate enough clamping force. Too long of a screw and they'll bottom out before creating the needed clamping force.
How did your son break three RDS sights? Were they early failures or long after he bought them? Did he drop them? Were they loose on the slide?
I have been shooting nothing but red dots since 2019 at a volume most people simply cannot match. I have two Trijicon RMRs, two Trijicon SROs, and one C-More RTS2. I have not broken any of them, even though one of the SROs hit the ground hard when I tripped, fell, and had to let go of the pistol to break the fall.
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