For me, I'd say alcohol. It's such a predictable high for me and not a good predictable high like heroin/benzos/cannabis (or even nicotine) but a sloppy, dirty, blah predictable high.
Alcohol is really only good for social stuff....but IMHO I'd rather go to a benzo pub than go to a alcohol pub. I think social gatherings would be more fun if everyone popped the benzo(s) of their choice and drank tasty smoothies and socialized. Maybe throw in some weak stimulants so everyone doesn't pass out too. Someday.....when I open my "pharmaceutical pub".....someday....