I am actually interested in this question as well.

I purchased one of the new B series shafts in the aftermarket, but I have not gripped it or tried it yet.

I am wondering if Team Titleist has tested it, and how it differs from the S+ series.

By the way, I have the S+ series shaft in stiff, and it performs better for me than any other shaft that I have tried.  Great work, Titleist!

I'm ver interested to know f this is available as well. Particularly the 80 x for a 913fd 3wd. 

Maybe it's available off menu?

Thank you  

Doug