+1 to what @ghdprentice said about trying before buying. My experience with audio equipment is that it's not so easy to equate price to sound quality improvement. On my $1700 Denafrips Pontus II DAC, I've tried 7 different power cords ranging in price from $15 to $600. The one that sounded best to me was a $94 Supra LoRad power cords. The more expensive Shunyata Venom V10 NR & Synergistic Research UEF Blue power cords were quieter, but also seemed to take the "air" and spatial cues out of music.
How good does my system have to be to realize an improvement with cables?
I've heard the difference power cables and interconnect cables in a highly resolving system so that's not the question. $200 for cables on a $500 DAC doesn't make sense to me. Wouldn't that $200 be better spent on a better component? At what point is an expensive cable the best choice? Spending $500 on a $15,000 DAC does make sense as the transparency and resolution of the component could be better realized with a better signal / power source.
My question is what's the percentage of the overall component's cost should be the cabling and at what point should it even be considered?
Or put a different way How would you know if your cables are your weakest link?