Don't forget about important safety feature that exposed hammer pistols have is that can be easily de-cocked unlike striker fired or internal hammer. One thing i noticed about all of these PLA pistol currently posted here is that most of them have an external safety switch. I don't know whether it's because they prefer it so much or possibly there were many safety concern like AD in the field. It could also be that internal safety design is currently too complex for them to make reliably. Maybe someone can explain.Usually to allow for both double action and single action fire. As they have different effects on accuracy and rate of fire.