I run steel cable. I see no reason to spend he extra $$ on it. Cable is stonger and durable and I have used it on every rig I ever had and it has never let me down. As long as replace it if it gets damaged the winch being used would never be stong enough to break it.
No it is not stronger, a common misconception.
A synthetic wire rope rated at 19000lbs is just as a strong as a steel cable rated at 19000lbs.
Synthetic rope doesn't rust or kink. The individual strands won't slice your hands open like a steel strand will.
Synthetic rope won't cause severe bodily injury when it snaps...it simply falls to the ground. Steel cable will take a off a limb, or worse.
Synthetic rope is easily repaired on the trail without having to resort to a handful of u-clamps and wrenches.
Synthetic rope is also a helluva lot lighter than steel. That means less weight up front to drag you down.
Steel may be cheaper...
.but that's the only place where it beats synthetic rope.