I am planning on using Flouro for my hooklengths this year, if I ever get out there that is, and decided to try my Drennan hook tying tool for the first time and see if I could make it work. I tried the 4lb vanish which I have had some sketchy success with first, and it tied a very nice strong knot. Then I tried the 2lb which I have had no luck at all with conventional knots, and horsed it up the first time and broke it. The second knot held up fairly well. I was able to break it, but I only used 9 turns and feel like the 12 they recommend would have done better. There's also a spool of Seaguar Invizx in 4lb that I've heard a lot of good things about, and am anxious to give it a try.