Whenever I go to an Indian joint for the first time I base my opinion of the entire restaurant on the quality of it's vindaloo. If I tell them spicy and it's what I would consider mild (which is probably what most Americans would consider spicy) then the restaurant is dead to me. If it makes my eyes water I'll come back.
This bit me in the ass (in more ways than one) on my last trip to London. We popped round for a curry after the pubs and I ordered prawns in a sauce that one of my friends said was a step above vindaloo. I've never seen something hotter than vindaloo on an American Indian restaurant. Er, meaning an Indian restaurant in America, not a restaurant in a casino.
Anyway, my friends got into a lively debate about religious symbolism in the Star Wars films or some shit, during which I was conspicuously silent. Cut back to me inhaling the prawns. This was the kind of spice where the first bite doesn't hit you until you're on your third (albeit when you're drunk and starving). My face was purple. My friend S thought at first I was choking. I was sweating profusely, a constant stream of tears and snot... when he asked me if I was alright I replied, "This is fucking awesome."