(This question/comment from a very successful tuna Charter Captain) ... We are using wind ons which we make and they are definitely nicer than knots, and better for the rods because the guide rings aren't getting knocked out like they do with knots. BUT, we've lost several fish to serving slip. After casting all day, the serving will get beat just like a knot does, seeming to work themselves loose after several hours of casting non stop. It slides slightly on the leader. Yes they are glued. When it slides, the motion of the leader through the guides opens up the braid and causes the leader to slip. Hookup, 30 seconds later the braid to the serving comes back with no leader. Bye bye fish. These serving issues are getting annoying. I guess what I am saying is I wouldn't trust the serve to last under load during a long day. [For what they cost] my advice would be, change them out fairly often. In my quest for a knot-less line system, I've learned that the demands on Wind-on Leaders for casting on Spinning Reels are much different than wind-on leaders for trolling or jigging. One of the biggest differences is the speed with which the Serves pass through the guides. (The speed also puts even more wear and tear on knots when casting, especially when you're going for distance.) The original Wind-On leaders and Topshots were developed so that there wasn't a loose pile of leader on deck during the end-game of landing a large fish--the idea was basic, allow the connection to be wound onto a conventional reel. In a spin-casting application, the Served connection can be brought in an out of the guides hundreds of times a day. And during the casting phase, for a 90 yard cast, the theoretical minimum speed through the guides is 65 mph. Realistically, in order to throw a lure 90 yards, I guess the initial speed needs to be 85 mph or greater to account for a non-perfect launch angle, air and reel friction and the weight of line being pulled off the reel. So I don't disagree, leaders should be inspected periodically and replaced as needed. And the Serve and Splice of a wind-on casting leader must be done very well. If done well, there will be less damage than with knots--and you get better casting distance, guide wear and tear, and strength. With well made Serves (see: http://www.360tuna.com/forum/f3/hollow-spectra-iii-commercial-windon-leaders-5187/) they will last for a day of casting and more than one large fish.