I was thinking of making myself a cupla coiled patch cords since you can't seem to buy them anywhere these days. Is there a fundamental problem with coiled cords or is it just that they went out of style and no one is bothering to make any quality ones anymore?
Coiled cables have bad electric properties compared to regular cables. I have an article somewhere that had cable tests complete with measurements, but it's in Germany. Result: Coiled cables = bad Monster Cable = not better than usual good quality cables and plugs.
Coiled cables are basically big inductors. More inductance means worse high end response (Inductors block high frequencies). It is generally desireable to keep cable inductance/capacitance to a minimum.
Coiled cords are also pretty good at receiving radio stations...and they never seem to get a station you like either.
Yeah, but they look cool. You don't want all that high end getting through to your amp anyway. I'd buy 'em if I could find 'em, that's for sure.