Originally Posted by
mdilthey
Is something like the mini 21" chain locks from Kryptonite my best bet?
For the same level of theft deterrence, a chain+lock is usually 2X+ as heavy as a Ulock. The chain you indicated only has 9mm links - even the cheapest Ulocks will have an 11mm shackle.
For your stated parameters, an inexpensive Ulock should be fine.