We use TSA approved locks and over the years have maybe had one or two apparently cut off or they failed to replace and relock them properly. For us that's a lot of flying between the two of us as we both have advanced FF status. No misgivings about security or theft prevention, they want in they'll get in. It's more about keeping the bag closed in transit. Cable ties work too but with the collection of locks we have.....the locks in many cases have outlasted the bags they initially came with....and we don't have to cut them off.