I always come back to Blue Bottle beans (specifically Retrofit and Hayes): I enjoy their espresso blends, surprisingly consistent. Four Barrel, De La Paz, and Sightglass don't do it for me though I buy their beans occasionally. I always come back to BB-- the variety in the espresso blends gets me, and they have never sold me old beans-- always dated, always 1 or 2 days post-roast-- which I can't say for the other newer places.
While I'm a fan of the beans, service is a mixed bag. Service in the Ferry Building, on Linden, and at the Mint Plaza is dialed in: courteous, professional, not too chatty but friendlier than a few years ago, like somebody reminded everyone they're in a service business.
Service at their new place on 18th Street in the Mission is not dialed in yet. The layout is different compared to the other shops in that there's no little side area near the register to wait to buy beans only, and they usually put my beans on the glass case left of the register as opposed to, like, giving me the beans they just sold me! And unlike the FB, Linden, or Mint, they don't pull espresso blends, but use a 2-paddle machine and profile SO beans, which can be interesting but not enjoyable to me.
Then few weeks ago, they were pulling Giant Steps shots and it was amazing! Most memorable shot in a while, but when I asked a manager the other day why they don't pull Giant Steps more, he said they never pull Giant Steps. Well I know somebody pulled me Giant Steps because they said it was Giant Steps, plus it didn't taste like cherries and tangerine pop rocks-- it was deep and rich and awesome. But the manager said nope, didn't happen. Not sure what to make of that, but I'll keep asking what they're pulling, and I'll keep declining their SO shots.