Tim,
I'll answer that one for Chad. If you want the DF97, 8125, 450+, etc family of materials, from Chad!
It has been my personal experience that the quietest bow strings I've had on any of my bows have been made out of TS-1+. My bows have been quieter with TS-1+ stings without silencing materials than any of the other FF type materials have been with silencing materials installed. The TS-1+ strings have been quieter yet after I've added cat whiskers. I must add that I've never used B50, so I can't compare TS-1+ to it.
Bill