Like so many others, I'm fine with either... as long as it is true to the story. (There is a difference between "realism" and "verisimilitude", after all; and whatever you think of the former, you must have the latter in a piece of writing -- at least, anything beyond pure farce -- or what you're dealing with is pure bilge.)
As for "twist" endings... frankly, I think they only work if the writer has put their work in on it... that is, they must "play fair" with the reader, and have that twist prepared for in subtle ways, so that it isn't false to the story. Otherwise, you're dealing with (again) something similar to the unjustified deus-ex-machina, which has got to be one of the cheapest tricks in all literature. It's a lie and a cheat, and nothing more. And that is where the writer's work comes in: giving all those clues, whether it be in specific choice of phrasing, intimations, foreshadowing, what-have-you... but still surprising the reader with that final unseen, but inevitable "twist". That, children, takes skill of a high order, and is a good part of why stories which manage to pull it off remain as entertaining and fascinating (and sometimes more so) on further readings as on the first.