I sun up acouple of B 500 endless strings for my Fedora Extreme and what a pleasnt,quiet string. I spoke to mike Fedora and we were talking strings and he gave me a recipe for a 14 strand B 500 and I am thinking the 5 fps I am losing going from a FF string is a good trade off for a quiet, pleasant bow to shoot. I made the string 3/4" shorter than the FF string so I have kinda compensated for stretch. I compared penetration between the 450+(10 strand) string it came with and it really doesn't drive it any further into the target.