Are manufacturer AC cables good enough?

not saying a different result can be had. But different does not mean better.

No, different means different. Whenever two things are different one is of necessity better, the other worse. You admit there’s a difference. So what you’re really saying then is you don’t know which is which. You don’t know what you’re hearing. Otherwise you would know one is better than the other. But you don’t. You only know they’re different.

Glad we cleared that one up.

They’re good enough. My rule is simple. If there’ s a long debate about a tweak. Leave it. Invest in what clearly matters.

About once each year a skeptic is brave enough to try and figures it out. At that rate by the end of the world the debate will be resolved.  ;)

Gosta: Your rule is simple indeed, but flawed. You base it on a debate from other people, AND, you give it a long time to develop. Why not “solve” it once and for all: try something for yourself. Unless you don’t trust your ears, that’s really the only way to know.

And what “clearly matters”? And why is it different than “a tweak”? More importantly, why do you think this “other people” never “invest” in “what clearly matters”? 

A general rule to follow is the more audiophiles’ hair catches fire the greater the odds are that the tweak works.