G'day Guys n Gals,
I was going to buy a disc lock for my bike some time ago and the bike shop owner suggested I get a security padlock and a heavy duty cable, with swaged ends, instead of a chain. He believed that a thick cable is far harder to cut with bolt cutters than a chain, especially if it is covered with a plastic tube that is too large for the average bolt cutters to get around. He also suggested I get some small pieces of pipe cut to fit over the loop of the padlock, again to prevent bolt cutters from cutting the lock.
It all sounded like a good idea but I never leave the bike anywhere it's going to get stolen. I take it out of my garage, ride it and it goes back in the garage.