So I'll go ahead and make this comment and if you disagree, it's ok.

My father is a retired physicist, a particle physics physicist. He worked first in the academia in the United States, then in Italy, then in Switzerland, where he worked for the CERN.

Particle physics involves quite a lot of testing and experiments with cutting edge technology. Generally, the business is about taking particles, and making them collide so that you can analyse the "debris" and get a sense of what is in the original particle. To do this, you need very expensive receptors. I'm talking about 1-500 million $ thing, depending on the project and the university/research center you're in. Then you have to transmit the data retrieved from the receptors to the computers via optical cables. In a minor academic lab, the distance to cover is around 20-50m. At the CERN, it's around 1-5km.

At this scale, cables do matter. Let me give you a few examples of that:

• Sometimes, the original information is duplicated and goes through different cables, so that no information is lost during the transmission. The information received from the cables actually differs.

• According to the CERN technicians, cables do need a "burn in", and tend to under-perform right out of the box.

• When the precision required is around 10^-10, changing the cables of some gear made a drastic difference.

• Most cable can't withstand long transmission distances. Information is actually lost when a poor cable extands too far. Electrons are much more volatile than people would think.

So, there you have it. This is from a discussion I had with my father a while back. Of course, for your 5'000$ setup, it may make no difference. But it's silly to think that optical cables are all created equal. The only thing is that it will only make a difference if you have a 1M$ gear, and only a difference that your ear won't notice anyways.