Hi Mate,
To many factors come into it to talk about it really.....
Depends largely on location....also whether you are landbased or boatbased.
A landbased king of 20kg plus will bring a grown man to his knees....
I was on the receiving end of numerous bust ups on 100lb mono straight through.
Both kings & GT's are just such dirty fighters....Both will slice through leaders in an instant....I hooked one recently in Fiji that spun me around and sliced through a 100lb twisted leader...under 15kg of drag...!!!
The boys on Nomad are now fishing 170lb braid to try and stop some of the beasts up at Shoalwater Bay.....The power they have is just unbelievable and the country they reside in isnt friendly.
They are all great fish at the end of the day but for me watching those big black GT's smash a 150g popper is just about as good as it gets.
I can see you love your barra....What about the bream?....you have left them alone for a while....
Cheers
Pete