I dont use them but for me they are a temporary/emergency solution for when you throw a shoe and need to get out of the mountains to a place you can replace the shoe
Make sure your stirrups aren't forcing your toes in, toes should be pointing in line with your knee cap. I ride longer stirrups than most probably do, with my legs hanging neutral and feet not in the stirrups, my feet are slightly lower than my stirrups, rotating my foot up in the front lands...