When I as there in 2003, I sat around for long periods of time taking flicks and just looking like what I was doing was normal and legal, (and most likely it is) and no one said shit to me.
As far as a specific place, there were a few nice outdoor spots. My main problem (and a problem with benching in general) was the unsymaphetic commuters, who ruined many shots.
I made a point to not have markers or paint or drugs or any illegal shit on me.
However, the one time I walked into a station drinking a Morretti, my man with the automatic weapon was like "nah, nah" in Italian.
I saw lot of POISON burners and one cat (CA?) that I can't remember had the city on such smash.