One thing with these clips is to replace them often. If you fish all night with a rosco clip or whatever the next night you toss it in the trash. Or you tie a new leader with a new rosco.
Im finding that folks who've had failures with the fast clips, are usign the same clip over and over or instead of throwing away a used clip are retying with that same clip theyve used for a few outings..
Clip only good for an outing... using the same clip on the beach that you had on last night while jigging the canal with a 6 oz jig is asking a bit much from a clip.. Retie. Throw away the old ones, new outing new clip, good fish new clip, new leader new clip..