Dime, I have never had a salmon break a hook, straighten, but never broken. I use Tiemco's or Mustad and occasionally Daiichi. If you romp down on the hook when placing it in the jaws of the vise it puts a score mark near the bend and weakens the metal. Its almost like scoring a piece of glass.
I fished with 12 lb tippet last season and had a few fish straighten hooks during that early season run.