Today I found a failure on one of my CHPWS v3 plates.
My Holosun 508T battery was dying (unexpectedly soon...) and so I removed the optic to replace it. I then noticed the threaded posts had sheared off the plate and came out with the screws. The plate has 4275 rounds on it total and I last had the plate off in November, about 2000 rounds ago, so I cannot specifically say when the failure occurred. The gun has not been dropped or otherwise abused. I noticed no loss of zero during that time.
Unfortunately, the MOS plate screws stripped out this morning while trying to remove them... Hooray. I've reinstalled the optic for the time being -- my thought is that the screws plus the bosses on the plate ought to keep it on there. However, I'll probably be replacing the CHPWS plates I have with steel FCD plates once they're available.