I've ditched using a fabric softcase since it was always too much worry if the airline would break it by accident or anything, and why ruin a good trip, and try to pack the skis with clothes etc.
http://cozywinters.com/shop/st-s1.html
I've been using a SporTube Series 1:
http://cozywinters.com/shop/st-s1.html
I like it and haven't had any issues. Sure it is a small pain to fit the skis into the box and hold back the run away prevention devices, but it is worth it. It can also be bungee corded onto a luggage rack, not that this is any sort of advertisement, just letting you know my positive experience