You can measure, but the figures I posted are accurate. They appear to sell 4-10 feet versions. The figures I posted are for the total loop (both wires).
They are not buying them because of the resistance because they don't even know it is there. They are liking it because of the resistance. It would swamp every other property of the cable. I think Eric is right, it is a tone control that cannot be changed. If the most common change is to raise the mid-range, is that not normally a change that people prefer at first? I don't know if that would be a long term preference.