add a leaf for fat bobs garage

if im buying a lift off of fat bobs garage it gives me the option to pock between the leaf springs. it gives you these two options ( standard add a leaf and longer add a leaf ) how do i know whoch one to choose and what didference would it make?

 

Longer ones are supposed to be a better ride and not break as easy as short ones might.
Short ones give a stiffer ride but tend to sag less over time like the long ones might.

 

ok thanks!