The choice of materials and production technique make a difference, no matter what the category or industry. Is a $600 Accurate fishing reel a better performer than a Zebco $89 fishing reel? Absolutely! I could not have landed that 150 lb. bluefin tuna with the Zebco. This also applies to inter connects, speaker cables, and power cables in the audio industry. As with everything, there are diminishing returns as you move up the scale in price. However, as with nearly all product categories, the higher technology and materials applications are, to some respectable level, trickled down to the medium priced products of the series. You get very good value in about the middle price range of the product line. No matter what your budget is, for audio interconnects, speaker cables, and power cables you will be rewarded with improved audio performance when stepping up the chain to at least a mid level cost of goods. Your choice of brand preference, of course. All of the established brands offer good quality products.
I became a believer in quality cables back in around 1990 when I replaced my Discwasher Goldends (yes, the record cleaner brand, Discwasher, came out with an early iteration of step-up grade connecting cables in 1979) with early generation of upper-end Audioquest interconnects. It was a revelation of musical discovery. I was amazed and astonished at such an improvement in audio performance through interconnects. I have made several upgrades since and there has always been a realized improvement. I am very satisfied now with what I have and all of my interconnects, speaker cables, and power cables will likely be with me for the rest of my life. Cables do make a difference, all of them.