Depends on the brand. U.S. made cells are 1.55 aH since they all come from the same factory. Foreign cells have always been less in their rating. I've seen 1.5, 1.4, many claim 1.3. Many do not have their stated capacity.
If you want to know how many amps you can pull out of them, figure a max of 2 amps. Some will deliver 2.5 but not reliably.
Check out some of the CR123 battery tests here on CPF.
YMMV.