The problem with using a TSA lock is that other people have easy access to your weapon without your knowledge. I've never used a TSA lock when I fly, have never had a problem.My understanding is that you are NOT supposed to put a TSA lock on the gun case. Only YOU are supposed have the key or combo for the lock. You must remain, when asked, in the screening area to provide the key to the TSA agent should he desire to check the inside of your gun case. The key will then be returned to you.
Well, I'm no seasoned operator or body guard, just a local LEO (retired from LE now), never had any trouble or issues on planes, trains, or automobiles. Don't personally know anybody that has either. I'd rather keep my gun with me all the way to the airport when I fly out and have it right there waiting for me in my luggage when I arrive at my destination.Avoid it. Best to overnight or two day the weapon to yourself at your destination. This is the approach seasoned operators and body guards take and it works fine. No issues with planes, trains or automobiles.
Robert B - If your smart you'll use a lock box with a cable and wrap the cable around your suitcase's framework, much less likely for that small lockbox to walk away if it's attached to a bigger bag.