I have used the Feathercraft furled leaders for about five years. They last and last and save you $$ over the long run. They are terrific for both warm water and cold water applications. I use the sinking leaders (available with a micro swivel to avoid twisting) and simply add 2-3 feet of tippet and off to the races! The floating leaders are also my preferred leader of choice. I use the 5ft. leaders and simply add tippet, usually 2ft. of 4X reduced to 5X or 6X for dries. As an additional benefit the leaders add a little extra “stretch” to reduce breakoffs.
The only down side is that if you are fishing with a single rod it’s a pain to have to change everything from the fly line down to go from dry to wet (or reverse) as you react to the feeding preferences of the fish. I spend a lot of time in my pontoon and generally rig up two rods to avoid the problem.