Another vote for copper nickel. Bends and flairs easy. It will work harden but is much more forgiving than steel. Making up lines is really pretty easy. You have the originals for a pattern and it's usually possible to reuse any brake-line blocks, just be sure and get new fittings (and remember to slide em onto the new line before flaring, don't ask why I say this).
Good Luck,
RonR