Unless you really, really, really (really) love your personal skis, don’t ship them down. Just rent (borrow) a pair if you’re in McM. Plus storage is always a problem.
If you’re going to Pole, we have plenty of them here and rumors of bunches of new ones coming in early this coming summer season, though you may want to bring your own boots for comfort and warmth.
One other thing to remember, is that when temps are at their coldest in McMurdo and Pole, cross country skis will feel like you’re dragging your feet across shag carpet (unless you weigh a 1000 pounds the pressure isn’t high enough to melt the hard frozen crystals to get the usual layer of water you need to glide). I know there are those who love skiing in Antarctica in the height of summertime and then there are those like me who winter who would rather walk.