I have noticed that there is quite a bit of variation in the way flights are served up in brewery tasting rooms. Some offer a fixed number, e.g. 3, 4 or 5 (served simultaneously). I have personally seen up to nine (Thirsty Bear Brewing Co. in SF, CA), although a friend reported an experience with 24 (!) with photographic supporting evidence (long since lost in memory and the stream of texts--only the number remains). Some give you a glass and let you refill it X number of times, with or without "chits." Some just expect you to buy 4 or 5 oz servings one at a time. For the cognoscenti, what's your preference?