use 15lb Vanish fluorocarbon for most of my BB fishing. Tough stuff with lower stretch. I do like some stretch for fighting the fish and getting a little shock absorption.
If I go deep (say over 30 feet) then I switch to 10lb Fireline. Once I get that deep I want to be sure to feel the bottom (Fireline has great sensitivity) so that I don’t let out too much line and start dragging the bouncer.
Fireline is also thin diameter so cuts through the water better and typically allows me to use a little lighter bouncer.