I did this after reading about a young person killed in the UK by a runaway aircraft - yes a freak accident but one that would have been avoided if the owner of the plane were using a PCM Rx set to idle on failsafe.
Ever since then, at f3a comps in the UK, it has been recommended that CDs check that failsafes are set to low/stop on the throttle, before flying starts.
I believe that this was suggested as a rule change to the FAI, but I don't know what transpired subsequently.
Just as a rather shallow aside, i use pcm (JR) receivers for everything--have done for many years, and ,apart from a couple of instances of range problems detected by ground checks(cured by re-routing the aerial),have never had a problem.
And I have to admit that my initial reason (again shallow) for moving from ppm was to avoid glitches spoiling a pattern flight, which the change most definitely did.