Katz’s is great and Langer’s is even better. My two favorite pastrami sandwiches in the whole wide world.
The Refuge is the best that I’ve tried in the Bay Area. Thick-cut (which I consider very important) and to me invokes Katz’s or Langer’s better than any place else. Certainly not in their class, but close enough to scratch my pastrami itch. There are two branches: San Carlos and Menlo Park. If you get your food at the San Carlos location to-go, you can eat next door at Ale Arsenal, which has an excellent craft beer selection, though both locations do have a decent Belgian beer selection.
I don’t find Sauls, Wise Sons or Wood Tavern to be in the same class as The Refuge.
