Bear in mind there is a strength difference between a sewn spectra factory sling and a tied mil spec 9/16" sling. The former is 27 kN, while the latter is 11 kN less 40% for the knot or about 7 kN. On the other hand, you may clip a shoulder length runner to the cam to extend it and that is no stronger, either, but you probably change them every couple years or leave them behind on raps.