I've been using furled leaders for 5 years now and absolutely love them. They aren't a commercial hit because it takes just minutes to make one and are incredibly inexpensive to make - so you can experiment to find just what you want. I have some that are now 4 years old and are fishing just fine. I just add tippet as needed and keep fishing them - and I fish 100+ days a year. I've never broken one but did have to replace one after I got it caught up in a bush and it frayed out on me (operator error).

There are lots of folks here that can help you to build a furling board to make your own, just ask! Also - just make them out of 6/0 uni thread and you're good to go.

I've settled on 5' length for everything from 3 - 5 wt. In 6 - 8wt I do like them about 6.5 feet long - but that's just my preference. There are no hard and fast rules for furled leaders.

Fad? No. Great idea that's been rediscovered - absolutely!