Paul,
I generally use the same number of turns for all sizes of leaders, which is about 5-6. As long as the knot really "bites" into the fly line and tightens well, my experience that this number will work well.
I have used the knot for coated wire bite tippets for pike fishing, but never mono-to-mono. A large part of its strength comes from the mono gripping the coating of the line it's tied on to, so I'm not sure mono-to-mono would work.
Martin
