I have not used those. Sounds interesting.
I use scaffolds.
I have installed on steep roofs since 2001.
We used to use ropes and harnesses. It is hairy and scary and hurts and tough.
--Both your hands are needed just to properly manage the climbing gear, yet you need a third hand to work with tools.
--Even if you are positioned well and working, where do you keep your materials and tools?
--If you drop anything, it slides and tumbles over the eave/gutter and down....onto who knows what.
And yes you WILL drop things, including heavy items.
Since 2005, I have a scaffolder set up a scaffold on each steep job, under the array.
Usually around $1,200.
Worth every single penny.
It is as much, or less than, my usual adder for installation labor on a steep roof.
My labor is 1/3.
We just walk materials up the scaffold as they now have stairs, or hand them up level by level.
You could have a seizure and you'd likely just slide onto the scaffold.
Also i dont have to store it, set it up or take it down. That is all not my problem.