We have the BAL Accuslide cable system on out bedroom slide (the other two are big ones and use rack and pinion). After ten years and lots of trips in and out there has been only one problem and that was when the tip (mushroom) pulled off of one cable. The slide continued to work. I found replacement cable sets on Amazon and fixed it myself using 1/8" cable clamps instead of the supplied crimp anchors.
I carry a spare cable, but don't really think I'll ever need it. The one that failed seems to have just been within the 1% manufacturing error rate.
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