I have never used PCP but have experience with analogues like 3-MeO-PCP and 3-MeO-PCE.
Surely part of the stigma must be that most info people have on PCP (disproportionately) comes from horrible news stories about manic psychosis and disturbing consequences like a user attacking people and resisting arrest with 'superhuman' bezerker strength, or cannibalism, etc.
So yes, news stories tend to report on that and not on the guy scrupulously using a known dose of PCP with good and 'safe' result.
Those horribles reports lead a life of their own and produce even more absurd things being imagined and spreaded as urban myth.
Additionally, PCP is notoriously eyeballed via solutions and dipped cigarettes, and confused with formaldehyde as both have the nickname 'embalming fluid' and more of that incredible stupidity. So overdoses are not surprising under such conditions, making matters worse.
The other side of the story is that the reports are based on or a consequence of very real risks: PCP and related compounds are not really forgiving, otherwise the overdosings wouldn't turn out so bad. Reasons for that are probably that they are quite potent dissociatives - highly effective - and also act on dopamine which apparently can lead to mania and basically stimulant psychosis when the doses are not really kept in check.
And there are other issues as well, like the comedown can potentially be pretty rough for some... it can stay in your body for a very long time since it dissolves so well in oils and fats (so fatty tissue in the body), that can lead to chronic effects having an unusual profile / constellation... but how that works exactly is IMO not clear. Buildup of metabolites could lead to partial desensitization (maybe dissociative tolerance but less dopaminergic tolerance, making effects and side-effects shift in a sketchy way), and not being able to detox quickly and well from it can play an extra role in psychotic episodes.
(By the way I also think that people who have general dissociative tolerance could have issues with that since they may require higher doses but are then not tolerant to the dopaminergic effects...)
In the moderate to high dosage range there is also the tricky combination of severe dissociation making you 'absent-minded', amnestic (loss of memory - I guess... anterograde?) and well, a bit zombified or a little petrified... but unlike some other dissociatives, PCP and alike compounds tend to make people stay mobile, so they can still walk around and do weird or dangerous things while mentally they are off to some place else. Definitely a reason to have a sitter present, where ketamine or DXM tend to make a person lie down eventually, and keep to himself.
And finally, the dose-response curve can be a bit steep, steeper than for other dissociatives.
I did find that qua effects 3-MeO-PCP at a not too high dose can feel very peaceful and Zen in an empty way. But it is treacherous, or well better said 'false' if you look closely... Real zen is rather about mindfulness and not mindlessness... but still, both seem to feel like unity and a 'that-ness' which can lead to nothingness.
Anyway, that quality does feel pretty 'pure', less dirty than ketamine and much much less dirty than DXM. But, if you are not careful, also very crazy.
