Juan - if you're talking about GT poppers (say 100g+) and you're targeting 15kg+ fish, I'd get the biggest size available in the SJ41 or SJ51 which is 11/0. I wish that these came in a 12/0 or 13/0 and the fact they do not is the main reason I have pretty much switched to the Fisherman Spinoza in 13/0.
These are both short shanked hooks but you don't need to use assist cord to attach them. You will find that two split rings works well and unless you have a swivel off the tail, you'll need two to make the hook sit either pointing up or down (unless it is an opposite eye hook like a Decoy Sergeant). if you want sergeants, go for the 8/0.
There is zero consistency among the various brands for their hook sizes which is very annoying. It means you have to see the hooks to work out what size is suitable.
Just one tip when putting a split ring onto the SJ51 or SJ41s - do it fast!! These hoks have a very heavy guage and if you take too long doing it, you will disform the split ring. This is one reason wy some people prefer assist cord. The problem with assist cord is if there are mackeral or wahoo around, it won't last long.
