I have a 8yr old "battered" hard shell samsonite that was easily opened when locked, was raided once in LAX not by security but nothing stolen, i then purchased a good quality brightly colored cut proof strap with combo lock and TSA lock several years ago, 2-3 overseas trips per year and no evidence of tampering since then. On my wife's case we padlock the zip handles then cable tie zippers to handle of the case, a preventative that does not allow zipper to be forced undone and re-zipped, ok the cable ties can be cut but it may deter opportunistic thieves and you also know if the case has been tampered with.