??? Full Loom vs Mix ???

The manufacturer will of course tell you that for best results you should use their product throughout your system.  Heaven forbid that another brand gets in between theirs and prevent you from reaching audio nirvana.

Some really high end components include custom speaker cables, power cords, etc.  You should probably throw those away and get a full loom of something else.

As you may guess, I'm a bit of a cable skeptic.  Not in the sense that they are all the same, I can hear audible differences between cables. 

However, I would rather pick up good used cables at a heavily discounted price and piece together a system with high quality cables of different brands than to pay list price for a full loom of cables throughout my system. 

If you have the funds to do so, and it matters to you, I don't think it's a bad thing and certainly will look better than the mess of cables I have behind my system.

I have never had a full loom of any brand.  I let my ears do the talking when it comes to what I purchase. So a couple of years ago I, @blisshifi suggested I buy a Silver Sonic Mirage USB .  I did and it was really good.  A couple of months ago I tried a Clarus USB that retails for twice as much.  I went back and forth with it and the mirage and ended up sending it back.  So right now I have a Silver Sonic, some Clarus, an Audio Art and an AQ cable in my system.

Your equipment isn't made with the same internal cables, even if you use the same equipment brand. 

Your equipment may not have cables at all internally, sone very high end equipment commonly has only PC traces. 

There are different loads all equipment are designed with, the cables should be transparent making those loads exactly the same at the inputs and outputs.

RF negation is real but with quad interconnects and good ground and insulation it's not the problem it used to be. 

Line level signals next to power lines can change signals with low quality cables, but not good cables.

How does the cable manufacturer of very high end cables know exactly what interconnects/speaker cables you need unless it is tested in your system, answer, there is no way and if the cable does make a difference in the sound it is only negative a perfect cable will only make no difference in the signal.

Just go with what sounds good, don't get caught up in the silliness. 

I am going for full loom of nordost Norse 2 line and each missing link I'm replacing is improving my sound. Interestingly a huge jump happened when I swapped my Transparent Musiclink Gen 5 interconnects between preamp and amps with Frey 2 interconnects. Is that because Frey 2 is way better cable or because it was the last remaining non-Nordost analog cable in the set? Not sure, but sounds amazing. 

I use Nordost Tyr 2 XLR, Frey 2 power cords on DAC and amp, Heimdall 2 power cord on a streamer. 
Speaker cables are Audience FrontRow. I use AQ Diamond USB and Purist Audio Designs Ethernet 🐈‍⬛ 7

I never had a full loom but got very close with Acoustic Zen cables. I really liked their Absolute Copper XLRs but when I tried adding the matching power cords and speaker cables I hated the cumulative effect. I can accomplish much more balanced presentation with mixed cables. I am curious though to try Tyr 2 speaker cables to see how they compare to Audience and how the sound signature would change. I have a feeling it would work out just fine. But I’m content with my system now and don’t feel like disturbing the synergy.