Generally when my friends and I have a night in drinking we each get through around a 1 litre bottle of wine. I drink spirits on nights out and at parties, and I'd say around half a litre of whiskey is my limit - about that much has me stumbling around, feeling nauseous, headachey 'i want to go home' levels of drunk. Not sure about other spirits as vodka makes me feel sick and I don't really like the taste of rum or gin.