I had sort of "OK" service at Trek store in San Jose. And I never had any good service in Cupertino shop (which is exactly why I don't go there anymore). Both Performance stores (in Mountain View and Campbell) have decent service. Mike's is good on one day and totally horrible on another.

The places with good service are also BikeSpring (Mountain View) and Bike Connection (Palo Alto). Also Bike Connection seems to be really busy these days -- a friend of mine dropped his bike for service over there last week and they gave him an estimated completion date of this upcoming Friday. Not sure why.