I've never used the gunnebo hooks, we just use regular 6ton shackles. same idea, slings don't have to come of the hook each time. We have a ton of slings, but theres usually 2 10 ft attached to the hook. This is especially better if you have no choice but to tie in the hook. wire the gate on the hook shut, and its a lot safer to tie into the hook.
Get yourself (2) 10s, (2) 15s, and a 20 and you'll be able to deal with just about any tree. Don't use the slings for anything other than crane days, inspect them and let the crane op inspect them before each use, and you'll be fine.
Get yourself (2) 10s, (2) 15s, and a 20 and you'll be able to deal with just about any tree. Don't use the slings for anything other than crane days, inspect them and let the crane op inspect them before each use, and you'll be fine.