For cross border travel I would probably go with a hard case but for everything else it's just personal preference.
I simply throw a lock through the zipper on my soft bags if transporting a restricted and my hard cases are easy to lock, I think either would be legal even though the soft case with a lock through the zipper is pretty easy to get around if you want in.
Lately I've been using soft cases pretty much exclusively but I have a couple Pelican cases and some of the cheap ones from Canadian Tire or Walmart. Even my Desert Tech SRS only ever saw a soft case and it was in mint shape when I sold it.
Firearms are not overly delicate so as long as you don't plan to throw it or run it over with your truck a soft case should work fine.
Agrred! cross border has its own ste of rules although not officially. I would far rather put up with the hard case than someone at the border who figures they are a hard case. Hats off to those who protect our countries, but many of them are not 100% up to snuff on the actual nuances of the laws.