Like other posters, I've been using the cable/zip tie approach. TSA can get into the bag if they need to and it might (if I'm lucky) make somebody think twice about trying to swipe something from my bags. I don't put anything in my checked baggage that I can't afford to lose. Someone might find a cheap flashlight or an old Leatherman or SAK, but that would be about it. Anything valuable stays on my person. Even that Leatherman or SAK will be buried in clothes. If they want it that bad I'll make 'em work for it.