I can't think of any failures with these. I recall a somewhat recent thread titled as such, but it was user related IIRC.
Regardless, I am still too chicken to use one. 4x4 truck heck no, but perhaps a car with a splash pan.
The one on my Santa Fe was on there for 300K Miles (535,000km) and was opened/closed multiple times. It was also exposed to lots of terrible winter weather and would be frequently full of ice/snow in the winter as encountered during oil change time and it had 0 issues.
I followed the directions on all the vehicles I installed this on and used the included washer. I put them on by hand and then give it 1.5-2 turns with a wrench to tighten down to the position where I want the valve to sit and they never come loose.
I have had far more oil plugs leaking with their crush/sealing washers than these over the years just FWIW.