I saw 1900 at the NYFF with Bertolucci in attendance. I don't remember how long it ran (and it was very long), but I do know that it was cut for subsequent general release.
I saw Salo at the New York Film Festival. Brand new. I did know something about it beforehand: fascist Italy, the infamous Marquis, Pasolini, and the shit scene. When that scene came up, I just kept reminding me that the actors were just eating delicious chocolate. Just a spoonful of sugar helps...