I would never use the loop....
Like Ross said, a six foot length of 1 inch webbing secured with a slipped reef knot (or bow tie) works fine. You can also use them to secure the reef cringles if you have taper cut the ends. That way you don't have those ugly reef ropes in the sail.I have plenty of sail ties around my boat, often carrying a few with me when working on deck for lashing stuff down.I don't see any advantage to using the loop method... maybe a bit easier to secure, using a slipped half hitch... but the non loop kind are easier to make yourself.. no sewing... and you can cut them to whatever length you want. I'm thinking the twisted loop straps would be useful as ladder rungs if you tied them to a stanchion and hung them over the side. But, I don't have the energy to make a test run on that idea...I'll wait till I can find a teenage guinea pig.