If you’re a commercial installer, you’ve been told that you must use solid copper for trunk runs. On the other hand, copper-coated steel is fine for home runs, especially shorter ones. Did you ever wonder why?
The answer is “the skin effect.” RF transmissions only travel along the outer edge of a cable, not all the way through. On the other hand, DC power travels all the way through the cable. Proper DC power levels are important everywhere, but especially so in commercial installs where you can be working with much longer runs. If you’re using commercial equipment, you’ve got to make sure you’re properly powering everything.
Copper-coated steel is ok for short runs and home runs because there is little concern about DC power loss. The signal doesn’t penetrate through all the way to the center of the cable anyway.
Of course, it may be more trouble than it’s worth to carry two different types of cable and remember which one to use. There’s no harm at all in using solid copper for home runs, either.