This SAE article indicates that the XL1 is 1753 lbs dry, so lighter than the Mirage:
Hyper-efficient VW XL1 drives to production. Not sure where the ~1900 lbs figure is sourced from in the Wired article; I've seen the 795kg (aka 1753 lbs) figure mentioned in a few different sources.
The Atom is pretty impressive, though probably not a daily driver for most folks...
