I can only speak for SF. While SF does have a public transportation system it leaves a lot to be desired. It usually runs late or not at all. Sometimes it's faster to walk 40-50min than it is to wait for the bus to stop by.
SF is pretty much the best in the state overall for public transportation, except for maybe small portions of San Diego (like downtown or the UCSD area).
if SF is the best, i REALLY don't wanna see the worst. i've been to SF a bunch of times and every single time i have issues with the public transportation system.