With a few exceptions my humble town, Concord, has little to offer in the way of great food. There is a fantastic mexican restaurant, Los Panchos, that is indeed one of those exceptions and it looks like San Ramon is getting a "Los Panchos #2" As I was driving by their Concord location, which may actually be in the Pacheco limits, they had a big banner out front annoucing the new location.
The only drawback to Los Pancos is that it is take-out only. Hopefully this won't be the case in San Ramon.
There isn't anything bad on the menu and they are very consistent which is something I consider important.