I honestly haven't tried adding any kind of severe stresses on the cable or ends in a twisting or kinking manner... I bought a new OEM part and applied consecutively increasing loads on it (one end connected to a big game scale, and an "S" hook on the other end connected to weight plates. the shifter end "ball" broke at 140lbs...-actually as I added 10lbs weight to the 140lbs load. -that's a new, albeit probably "old stock" but it wasn't dried out and OLD like the one I replaced.
Next, I threaded the ends and attached my cable ends to each end, and ran out of weights at about 250lbs, so I continued the "torture test" by towing my old fullsize 4x4 pickup truck to the gas station about a mile and 3 stoplights away. (mind you, I live in South Florida where it is flat as a pancake, but even still, I managed to TOW an old Ford pickup truck with it! -which by the way is what Ford pickups are designed for... to be towed -with GM products

I don't think the ends could fail under any normal circumstances...
You're asking about the CABLE itself, if I understand you correctly?
after my "highly scientific" testing, I rested assure that the original cable was of sufficient integrity, and after installing and removing the one I used on my own mothers car at least 15x, I can tell you for certain it goes in and comes out quite easily, with only one hand required to engage or disengage the cable ends

 

Having " been there" a couple of years ago , I wish I had had this .

 

The cable is weak between the shifter and tunnel entrance, lifting the shifter too much for removal or replacement can crack the plastic right at the tunnel entrance making the cable worthless. New cable ends won't correct the broken plastic in this area. What's needed is an all metal cable that can withstand the tunnel heat and bend enough to allow installing it to the shifter.

 

Is this an A4? Sry...just breezed through.

 

This I wasn't aware of since the problem with the cable which prompted me to develop the ends / kit was due to the plastic end failing.

I understand what area you are talking about now though, and can certainly understand how that plastic could be damaged as you are describing...
The first thing that comes to mind is a standard morse cable, although the trick would be coming up with both front and rear mounts that fit the factory mounts correctly...
I'm sure I could do this, however, I would need to know there was enough demand first...

While the cable ends and kit appear quite simple, designing, prototyping, adjustments, 2nd, 3rd, 4th version... (about 15-20 trys to get it down perfect so that it will now work for anyone on the FIRST try and you can begin to see how something seemingly simple isn't quite so simple!

As for the cable, the thing that I realy like about it is the way it mounts to the brackets. (the retaining "staples" are sort of a PITA, but besides that, I like the plastic tabs. Although, I could foresee a threaded ferrule and knurled aluminum disc-like jam nuts that could replace the plastic pinch tabs??? In fact, there are a couple of ways I can think of which might possibly be used for this, but of course there's also an issue of cost. what would be the approximate value for a totally revised, cable mounts AND ends, all of which is absolutely solid and absolutely superior to the original part in every way. -no weaknesses, will never fail and extremely easy to install and remove?

If there are enough interests and if the appreciable value is high enough to include at least some ROI, I can put the C5 back on jackstands and start designing / prototyping immediately, otherwise, I can brainstorm with anyone who needs an entire new cable and perhaps through a cumulative effort we can come up with a working solution for the folks who need it.