Hi Dan,
It really depends on the set up that you are using, some anglers use 200lb leader with no problem but terrain play a big factor and you have to consider that fact, I am personally using 300lb Leader, if you intend to use any PE line or main line over 100lb i would suggest you to get a 300lb shock leader you defiantly needed in places such as Southern Oman but not in New Caledonia were you pop in deeper water a lot of time , that recommendation is based on my experience on the water and from what I've seen in the field.
Tight lines
Sami