Sorry for the late response, but I had to reach out to my buddies who are running the WE steps and get their input. First, no one has used anything but the ropes that came with the steps from WE. My one buddy who is very knowledgeable about Amsteel said that it doesn't stretch, so he wouldn't use it on the WE steps. I agree with this because when I spoke with Andrew from WE, he said the ropes helped the camming action of the steps.
Everyone I talked with has zero issues with them and is very satisfied with their performance in the field. One of the guys also uses his steps with a knaider and swaider and has little bumps of JB weld on the crossbar for the hook to sit in while he is using his Knaider & Swaider. The other guys have just put stealth strips on the steps to help quiet them down during transport to the tree. None of the guys do anything to the ropes except hang them on a tree for a couple of days to stretch them out properly.
If you search on YouTube, there are all kinds of videos on modifying or making holsters for the WE steps. I think once the ropes are properly stretched out and you can confidently tie the knot to attach them to the tree, these are an excellent option to sticks or screw in steps.
I hope this helps and safe climbing and hunting!
Roger