Fish line in day/night shades

Monofilament line over time would cut the grommets/guides (nylon) I believe. I used 120# braided kite string, 400 yds was about $13. I no longer have to do that since I got tired of doing them each about every 12-15 months, so we changed them all out for United Shades' roll up day night shades. At the time our RV was built, Tiffin was using brass grommets as guides on their shades instead of the nylon guides that United Shade used in their. The brass guides caused more failures for us as fulltimers since most of the shades were cycled 3 or more times a day. But I tried many strings and found the 120# nylon braided kite string was superior to all others.