An old thread worth bringing up. I tried my first set of Firecore 50's last week and these wires are FANTASTIC! Just the feel of the materials tells me they are quality and will last quite a while. The conductive core on the wires is very beefy, so I can understand why some of the fuel guys are using them. The car idles smoother and sounds great w/these wires. I had a small issue w/ the coil wire boot being too big and within 1 1/2 working days I had a new coil wire at the front door. Thanks for a great product and unsurpassed customer service.