I am a big fan of public transit, taking the train regularly to Sacramento and San Francisco to visit family, taking BART to the symphony or to museums in San Francisco and riding light rail and Muni in San Jose and San Francisco. But I am somewhat reluctant to recommend these services to some of my more fastidious friends, because Caltrain and BART in particular are more than a little grungy.
In the past 20 years, I have traveled on public transit systems similar to BART, and I have seen cars and stations in Taipei, Atlanta and Washington, D.C., receive upgrade after upgrade. In the same period of time, nothing has happened to BART, except that the 40-year-old cars have gotten dirtier, smellier and more worn. The windows have become so scratched that it is nearly impossible to read the signage at each station (especially because very few of the station signs are illuminated), and there has never been any interior electronic signage to tell where you are. The rails have become noisier and noisier, to the point where going around a bend in a tunnel is now acutely painful to the ears. The noise is so intense that any onboard announcements are completely indecipherable. When I take BART to San Francisco, I wear earplugs.