I was speaking with a representative from Powerslot a few months ago. That guy said that the only time you really need SB lines is if you're into competition road racing (not street racing, that stuff is both very dangerous and illegal. Like anyone here would participate in street racing, right? Thank you, we may continue). Most of the time, DDs dont come close to using the flex-control properties of SB, MUCH LESS needing said flex-control.