this is only my opinion but by experience all my personal guns are da/sa becose i like the safety of the double action on my gun i carry a fnp-9 so it has both da/sa and a deCocked for safety
the resin i like that is if i have to pull my weapon i control the hammer pull so if a have to let go of the trigger and the hammer falls it will not discharge my weapon
if i set my gun to single action and i dont have to pull the trigger the deCocked will let the hammer falls it will not discharge my weapon
the double action pull on my weapon is about 10 to 11 pounds and the single action is about 5 to 6 pounds !!!!!!!!!!