My 507C hit 4500 rounds yesterday. 4000 of which have been attached to a G17.5 MOS.
Zero has remained constant. Was zeroed on fitting and it still shoots POA/POI. This lives on my practice gun. Recently I've had access to lots of ammo but very little time. So its had sessions of 1000 rounds in 3 hours or so and a good few plus minus one hour 500 round sessions.
So far its outlasted at least one of my DPP's and two Docters.