For guns with two different chokes then most single triggers are not that easy to change from one barrel to the other so the two triggers tend to be more reliable for most. Some people have a problem dealing with two triggers. For them a single is best. Or to paraphrase what my father use to say some people can not walk, chew gum, mount a gun and select a trigger, the single trigger is best. For them the auto was made. Bang, Bang, Bang as they say.