Another supporter of quick links. Over 100K miles without failures. I have even used the same link on successive chains. I think 9-10K miles including many removal/re-installs is what I got out of one before deciding to trash it after the pins started showing wear grooves. I would guess that yes, it's probably the weakest link in the chain but proven to be strong enough. No difference in performance or extra wear. No medical issues that I can think of. Just look closely when you install them to make sure the link is snapped together properly as I have seen when showing non-mechanical friends how to install them that sometimes they have difficulty getting both pins in the slots properly. Easy to correct if they get it wrong the first time though.