This one is only 420 lbs. The way i see it you can't fall off the roof because the scaffolding will catch you, as long as i only work in the 6' range. Where as the roof hooks plenty can go wrong, what if the first ladder falls down? then i'm stuck on the roof. I think the key is attaching the scaffolding to the house. Sure it will take a lot longer but i have to do a lot up there anyways. Where would you put the materials, the tools?