I HAVE HAD THE SAME LOOP ON MY FLYLINE SINCE I PUT THE LINE ON IN MAY 2013. I HIT THE WATER AT LEAST EVERY 2 WEEKS AS BECAUSE IT'S CLOSE TO THE HOUSE AND I HAVE NEVER HAD A PROBLEM WITH THEM SLIPPING OFF. I DO USE FLOATANT ON IT AS THEY DO TEND TO WATERLOG, BUT I JUST PUT IT ON BEFORE I GET IN THE WATER AT THE BEGINNING OF THE DAY AND DONT HAVE AN ISSUE
The instructions say heat the shrink wrap with temperatures exceeding 230 F. A hair dryer failed to generate enough heat on my 4 wt line, so I tried a lighter. The later heated the shrink wrap to the point of almost burning it, yet when I pulled on it 12 hrs later, the leader loop slipped off. When I looked at the tip of the fly line, it was obvious it had been heated to the point of deformity; I had to trim it big time. I use shrink wrap on electrical connections all the time - no problem. The Cortland shrink wrap was a problem.
I've tried this product 19 ways after loosing fish to a loop failure. Crazy glue... more heat, more shrink tube...doesn't matter. What works is a real loop tied in place. Or.... I would rather use a LeaderLink than this product. I had these Cortland loops on all my lines and had to remove them all. I now use leader links and the problem is solved. Faster, easier, more reliable. If you a depending on these Cortland loops to be reliable you are in for a surprise.
The leader loops are easy to install and move through the rod guides pretty well. The problem is that the shrink wrap netting eventually becomes waterlogged and drags down floating fly line. I constantly have to apply floatant to keep the end of my floating fly line floating.