All the strings I have tried except for the Amnerican Made Cryogenic strings loose their brilliance after a few weeks or less. Since they are unique and have only been made for about 5 years or so you won't see them listed in the Banjo Masters Book. If you check out their website you will see lots of testimonials from well known players and their favorite sizes. When I had a festival I liked 9 1/2, 11, 12, 20 and 9 1/2 or 10, 22, 12 1/2, 20 w and 10. They seem to be just fine for my Stelling Also. The cryogenic treatment just takes away the weak spots on the string which causes string fatique and lack of purity over time.