I use the Z line for my tarp tie outs. A few thoughts and observations based on use in a windy overnight hang:
The line is very strong and it held up to about 30-40mph gusts
I used rocks on top of my stakes and one line was rubbing against the rock and the line freyed. So there is a durability issue if the line is rubbing against anything. I managed to find the issue early and re-tied my guyline.