I have a metal loop, in a junk box on my bow table.

I just do not see any need to screw a metal loop to a string when there are solid, easily made string loops available for pennies. They're lighter, giving you speed and can be adjusted to any length you want to tweak your draw length. I've heard several horror stories about the metal ones breaking strings, or flying off and hitting the shooter in the arm, head, etc.

No way one of those thing will be on my bow.