How long are you going to leave your bike locked up/unattended and is weight a concern?

A 5-6 ft chain with an inner tube for paint protection and a good lock is a lot better than a cable of any thickness. A 26x1-3/8 tube is about 6 ft long with the valve cut off and fits a 1/4-3/8" thick chain/1"-1-3/8" chain width. 26x2.x tube is good for the thicker/wider HD boron alloy chains.

Personally I use both a U-Lock and chain w/lock and my GF prefers using 2 U-Locks. BUT we use our bikes for multiple uses...short and long rides, shopping, commuting, etc. Depends if you want to take off the front tire, lock it with the rear tire, and don't mind your fork on the ground. And if you are looking at a cable to also secure your saddle...a chain can do the same thing, just buy a longer length of chain.