To date I have never had the set screw come loose on a quick connector. The problem with them is they do tend to loosen up and wobble giving some slop to your connection that will show itself as a lack of throttle response, even using the metal back plate and setting it with a slight hammer tap. Ihave used them on both ends without any trouble but it does tend to double the slop you will end up with. Istill use one on the throttle arm and a clevis soldered to the one end of the cable on a number of set ups. They work but there are better ways to set up a throttle. FYI, there are clevises that say solder clevis on the package, they are silver in color, much easier to work with then the golden clevis.