Catch is, I've seen some neat stuff, but not used it. I've bought things in the past that got lots of publicity that made them sound wonderful, only to determine they were a waste of money and not worth the materials they were made of.
However, beyond what I said above, 2 ideas have caught my interest:
1. I would absolutely not have this in a situation where it couldn't be left in its "stairs" form when people required it for safe egress.
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2.
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I've seen various versions of this, but this one at least is using some sections as storage. This could be scary for emergency egress, but if the railing was sturdy enough to take a significant amount of a person's weight, I think many could manage it. I would prefer to find someone who had actively used this sort of design (I recall it's been used on commercial boats) for at least a year and then asking them if they'd want one in their home.
Personally, rope ladders may look cool, but they're a pita to use (pita - pain in the
ass feet).