Given the background description of some cooking related query, summarize the question into a title

http://www.topsecretrecipes.com/Pizza-Hut-WingStreet-Traditional-Chicken-Wings-Copycat-Recipe.html has a copycat recipe for Pizza Hut's hot sauce (you can't see the recipe anymore as it was free to the public only until July 21). Anyway, the instructions says to use margarine to really get close to the original recipe, but butter is an OK substitute. What exactly is the difference between margarine and butter when making sauces? Is one better than the other (it seems to me that margarine is supposedly better -- but always thought that I should stay away from it)?
Hot Sauce: margarine versus butter