Your posts got me excited to try the Cheese Steak Shop. I wanted to post then, but figured I'd wait. Now that I know what I'm talking about...
I went to the University location in Berkeley, just west of San Pablo.
I can enthusiastically recommend it. Solid cheese steak. I've lived on the East Coast, not in Philly, but close enough that I'll warrant my haunts didn't lose much of the cheese steak concept in translation.
As other posters noted, the bread is flown in from Philly. The classic Amoroso roll. They do a good but not perfect job with the grilling. The familiar cheese/meat mash-up is delicious--greasy but not grossly so. The onions is where they lose points with me. A little more caramelization is essential. Of course, this is a problem that might easily be addressed by a quick word over the shoulder of the grill master.
The fries suck, but who cares? (I suspect they fry their fries in the same oil as their fish--whether by policy or aberration from policy I don't know. I could be wrong on this point.)
While this place doesn't quite equal the few famous Cheese Steak Cathedrals of the East, it would be a respectable entry in the genre in any eastern city. Anybody who says different is homesick.