I believe there is a challenge somewhere that if you can prove an absolute difference you win $1,000,000?
Conjecture is futile.
IMO you need to find out the qualities and flaws of the rig you are going to upgrade and learn all the qualities and faults of all the different metals and procedures of cable making to really get an idea of an expensive cable will work instead of a less expensive one. If you are not used to a cable being cryo'd, treated with Walkers, Deoxit, and the use of dielectric's, shielding, braiding. A cheap cable way be the way to go.