Sadly, the heavy rents in SF prohibit a lot of stores of the survivalist, hunting, and sportsman variety and you are already familiar with Tad Gear. Tad Gear is pretty cool and they have some interesting and quirky items and as already mentioned, REI has some decent stuff as well but neither of the two have an extensive Surefire collection.
San Francisco doesn't have any of the larger chain stores that a lot of other flashaholics refer to so TAD and REI are the only two that I know of. There are some classic Army+Navy stores, one on Market around 6th street and one in the Upper Haight but I haven't been in either one for a while. I'll keep racking my brain and do a few more searches and if nothing else maybe we can catch a beer or two should time permit.