Kev,
I have used the Magic tool for a couple of years now and I ordered the Petitjean thread, used in the DVD, from Lakeland Fly- Tying. It splits very easily without any fraying which, in my experience, can happen with some other threads. The secret appears to be to get the thread as flat as possible and this makes it easier to split. I have had some great days at Haddo using the dries produced from this tool and look forward to better weather to get out again.
All the best
Peter