In North America, Festool offers two kinds of Plug-It cables. The slightly more flexible version uses 18ga wires with less capacity, which is more than enough for all the sanders and some other Festools. The only slighter stiffer version of the Plug-It has 16ga wires with more capacity. This is necessary for more powerful Festools, such as the TS55, TS75 and some others.
For safety reasons there is a difference in the female end of the various Plug-It cables, so that the 18ga version will not fit the larger Festools. However, the 16ga Plug-It from your TS75 will work just swell with your sanders.
All of my many Festool sanders came with the 18ga cables, and they are still stored in the dark unused. For convenience I bought a few spare 16ga Plug-It cables so any tool using a Plug-It can be powered by any of the cables packed in my traveling Systainers or out in my shop.
Personally I have yet to find a disadvantage using a Festool sander with the 16ga cable. My assumption is that the hose is going to influence my movement of a sander more than the flexibility of the electrical cable.