I think Steve and Vickie make great points but note that although San Ramon does not have a downtown, there is one on the horizon and when that eventually does get started, I think we will see considerable increases in home values there.
Other than that, I would say that you need to look as much at individual neighborhoods in all three cities, as much as in the cities themselves. You may find better value in one Pleasanton neighborhood than in some San Ramon or Dublin neighborhoods, but the opposite could equally be the case.
Best advice - focus on the location and lifestyle suppport that best meet your needs.
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