Tried WeisCANNON Silverstring 1.2mm on my 001 90 at 62/60 and I didn't like it very much; no bite and the string was very flimsey, not solid at all. I cut it out after 3 or so hours.
Cyberflash 1.25, SPPP 1.23 were much better I think. And right now I'm on Kbaum Competition 1.2, and it's better than Silverstring in every way.