I wouldn't get terribly hung up on brands; Surefire batts are good, but so are a lot of others.
Generally, though, you should never have to pay more than $1.75 tops for a CR123 battery if you take the time to shop.
You'll always get the best deals online, and $1.00 to $1.50 should be the most you pay for most brands (except Surefire).
While some faithfully stay with Surefire, I think any of the name brands are predictably good.
At the same time, I've bought some Tenergys and Titaniums, and ALL of them have tested fine and to full capacity using my ZTS meter which I always use to verify a battery's state of charge for matching in multi-cell lights.
I don't care if I am using Surefires or Duracells or Tenergys or Titaniums, they ALL get tested before I pop them in a light.