FWIW, about a year ago I bought a slightly used Specialized Secteur (the aluminum version of a Roubaix) on Craigslist, and have been very happy with it -- though admittedly I don't have much of a basis for comparison, since it's my first road bike in pretty much ever. It's definitely not built for speed, but that doesn't sound like a major concern for you.
And welcome to NorCal.