for stopping i say they are useless because the front tires slide too much, but for $40 i say why not...they wont get broken/torn as easily as stock and it sounds like you need more length for your other mods.
I don't know of anyone that has ever torn or broken their stock brake lines. Thing about steel braided lines is that they feel more solid because the don't expand under braking pressure like stock lines. This can be a double edged sword... Yes, they will feel more solid, but they will be easier to lock up your brakes instead of braking under control.