[Porsche_monkey]

I suppose I should have stated that quality name brand outlets were assumed. I wouldn't use low cost outlets, some risk is assumed, and very little money is saved.

As an electrical engineer I have zero concern with a properly installed push-lock on a quality outlet.

But, I can see that if you are prone to worrying about this sort of thing, that a screwed on wire is superior. That's a given. On a protected 15 Amp cct the push-lock is fine.

As far as arcing goes, eventually arc detection will be required on all circuit breakers. But your concern, for an improper installation, is valid. Arc detection is now mandatory here on bedroom circuits. A very good idea.