I don’t share this view that NACA5 is inflexible or stiff. Lighting style flex it certainly is not, but as a cable, terming it “stiff” is misleading.
The definition of stiff ”is not easily bent or changed in shape; rigid.” Naim speaker cable can easily be dressed.
It does require some patience, but it is imho easily achieved. Either use a former or a trick sparkies use is to take a pair of pliers, hold in reverse, placing the cable between the handles and alter the angle and a nice action, with a little practice, can achieve the desired shape.
Important is to ensure the cable is warm, either a hairdryer, electric heat gun or even placed on a suitable heat source - don’t overdue it.
I have used it for >20 years, some much newer. Naturally it well suits Naim systems, which is why it should have full consideration. Used is frequently available, just ensure solder joints are sound or have them redone, it makes a difference.
Finally to the OP @Shanna I haven’t seen mention in this thread, that there is a good section in the FAQs if you haven’t already read it.