I squat in a power rack, and feel safer than if I were in a half rack for exactly what you said...no matter how much you screw up in a power rack...the bar is going to get caught...not only on the safeties going down but on the uprights with forward or backwards motion. I can't press in my rack because it is too low due to 7' ceiling, but that does not concern me at all. I don't think many people who have power racks choose to squat outside of them for no reason.