I use the Speer polypro webbing. Before I got the biners I just passed the webbing through it's own loop on the end and snugged it up to the tree. After just a few used I noticed that the loop and some of the webbing that passes through it was getting a little fuzzy. Not enough to be a problem, yet, but showing obvious wear after a few uses that continuous use like that might causes enough wear for failure. The webbing is a little abrasive against itself. I've not noticed any increased wear since using the biners...and it is a lot quicker the use.
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