For me, in my system, the difference was pretty big. The stock umbilical was quite veiled in comparison. I think it was more forward sounding, which wasn't necessarily a bad or good thing. Images were less distinct and flat sounding on the stock cord. And brightness has been an issue in my system; the big titanium Eton mids I use have very good detail but can veer off into brightness so I've to be more aware of matching other components and cables with the upgraded umbilical but I really can't imagine having to go back to it. For me, the RAL cable has been a no-brainer. Hopefully it will be worth it for you too.