I own 2, 25-30 ft. old monster speaker cables with the red and black banana pins already on them. They're a giant gauge in clear coating. I don't see any discolorations anywhere. My questions: Do they ever "wear out"? These runs are way too long. Can I simply cut them down and put new pins/spades on? I'm not experienced with a soldering iron, so are any replacement connectors "screw on" and are they worth a ****?