Ill start by saying I dont currently use furled leaders for any purpose (anymore)
Back when I was casting glass and bamboo (occasionally) and strictly fishing dry flies I would use furled leaders as more of a throwback of sorts to previous generations of casters... I really enjoy the light turn over and delicate presentation of the fly, along with the smooth loops and overall durability (read further)
However I stopped using them because they became expensive for the areas I was fishing, and I found that the odd larger fish I hooked would stretch the leaders into a coiled mess. Let me get back to the durability and my first comment in this paragraph. I often find myself fishing the smaller waters, lots of areas with overhanging brush, tight cut banks and wood. Seeing as I am in no way a perfect caster and I occasionally donate the odd fly to mother nature, I was finding that when I would get hung up I would have to cross the river to pick out my fly opposed to breaking it off (above mentioned coils under tension).
I would maybe consider using them again if I was fishing open water up stream dry fly everyday... however I dont, I doubt many people do around here. If you'd like to have a dedicated rod for these purposes I would definitely suggest them, I used blue sky and feather craft when I could find them. But seeing as I will also have spools of mono on me anyways I cant really justify the $20+ for a furled leader... but thats just my 2c