I bought this anti-theft luggage strap due to most of the reviews being positive.  Despite a reviewer stating the strap could indeed be loosened, I gave it a try thinking maybe that reviewer received a defective product or something.  However, upon receiving the strap, I discovered I was able to slowly loosen the strap once locked (the other reviewer who commented on this does a good job of explaining how, so I won't include the method here).

Having said this, the strap is still "okay" in my book.  I like the color and design on it, which makes your luggage easily identifiable.  Also, the perception an anti-theft strap gives may also, for the most part, be somewhat of a deterrent to thieves anyhow.  The strap appeared sturdy enough, but in the end, I returned it because it didn't live up to its advertisement...