I have the thickest cable Kryptonite lock you can get. Cable is 1/2" steel with a plastic jacket that makes overall diameter around 3/4" . It's so heavy duty it doesn't want to strech out at all. It still is in a coil after 2 years of use.
But like the old saying goes, locks are to keep honest people honest. I've gone the biker route and keep my bike in the house. Not an option if there's a woman in the house